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KCSE 2025 Chemistry Paper 2 Question 1 — periodic trends across Period 3 from magnesium to chlorine.
Chemistry • Form 4 • Periodic Table

KCSE 2025 Chemistry P2 Q1 — Period 3 Trends

Explain the Period 3 trends — radius, ionisation energy, melting points, oxides, oxidation number and SiCl₄ hydrolysis.

KCSE 2025 Chemistry Paper 2 Question 2 — organic naming and the flow chart for the extraction of copper from copper pyrites.
Chemistry • Form 4 • Organic Chemistry

KCSE 2025 Chemistry P2 Q2 — Naming & Copper Extraction

Name two organic compounds, then follow copper from its ore — gas C, the silica slag, electrolytic purification and the green patina.

KCSE 2025 Chemistry Paper 2 Question 4 — preparation of chlorine and a flow chart of its reactions with iron, phosphorus and alkali.
Chemistry • Form 4 • Chlorine

KCSE 2025 Chemistry P2 Q4 — Chlorine

Prepare chlorine from NaCl and MnO₂, then work through its reactions with iron, phosphorus, hot alkali, hydrogen sulphide, iodide and litmus.

KCSE 2025 Chemistry Paper 2 Question 3 — a Hess's law energy cycle for propane and a calorimetry calculation for butane.
Chemistry • Form 4 • Energetics

KCSE 2025 Chemistry P2 Q3 — Hess's Law

Define standard enthalpy of formation, build a Hess cycle for propane to find ΔH₃, then use Q = mcΔT to find the mass of butane burned.

KCSE 2025 Chemistry Paper 2 Question 5 — the Down's cell used to extract sodium by electrolysis of molten sodium chloride.
Chemistry • Form 4 • Electrochemistry

KCSE 2025 Chemistry P2 Q5 — Down's Cell

Extraction of sodium in the Down's cell — identify the electrodes, the role of the diaphragm and calcium chloride, and calculate the mass of sodium from 1000 kg of salt.

KCSE 2025 Chemistry Paper 2 Question 6 — electrolysis, Faraday's law and electrochemical cells.
Chemistry • Form 4 • Electrochemistry

KCSE 2025 Chemistry P2 Q6 — Electrolysis & Cells

Electrolysis of copper(II) sulphate, a Faraday's-law relative-atomic-mass calculation, electrochemical cells and the corrosion of aluminium versus iron.

KCSE 2025 Chemistry Paper 2 Question 7 — rates of reaction using collision theory and a volume-of-gas versus time graph.
Chemistry • Form 4 • Reaction Rates

KCSE 2025 Chemistry P2 Q7 — Rates of Reaction

Rates of reaction — the effect of pressure and temperature, the ethanoic acid and copper(II) carbonate reaction, and reading rate off the gradient of a tangent.

KCSE 2025 Physics Paper 1 Question 1 — a micrometer screw gauge measuring the diameter of a steel ball with a positive zero error.
Physics • Form 4 • Measurement

KCSE 2025 Physics P1 Q1 — Micrometer Zero Error

A micrometer with a +0.02 mm zero error reads 0.31 mm — correct the reading to find the true diameter.

KCSE 2025 Physics Paper 1 Question 10 — a vehicle speeding along a dusty road leaving a trail of dust rising high behind it.
Physics • Form 4 • Fluids

KCSE 2025 Physics P1 Q10 — Dust Trail

Why does dust rise high behind a speeding car? Fast air, low pressure, Bernoulli.

KCSE 2025 Physics Paper 1 Question 11 — an object decelerating uniformly from 3 m/s to rest over 10 metres.
Physics • Form 4 • Kinematics

KCSE 2025 Physics P1 Q11 — Deceleration

An object slows uniformly from 3 m/s to rest over 10 m — find its acceleration with the equation of motion.

Sources of energy compared — coal, oil and natural gas as examples of non-renewable fossil fuels.
Physics • Form 4 • Energy

KCSE 2025 Physics P1 Q13 — Non-renewable energy

Name a source of non-renewable energy — and understand what makes coal, oil and natural gas non-renewable.

A coin resting on a smooth card that bridges the mouth of an empty beaker, with the card being flicked away horizontally.
Physics • Form 4 • Forces

KCSE 2025 Physics P1 Q12 — Inertia coin trick

Flick the card from under a coin and it falls straight into the beaker — see how inertia explains the classic coin and card trick.

A heat problem involving melting ice with heat supplied by a heater and hot and cold water being mixed to reach a common temperature.
Physics • Form 4 • Thermal Physics

KCSE 2025 Physics P1 Q15 — Heat & mixtures

A full Section B heat question — specific heat capacity, latent heat of fusion, and finding the final temperature when hot and cold water are mixed.

A smoke-filled room with hot smoke gathering near the ceiling and a person crawling along the floor towards the exit in the clearer air below.
Physics • Form 4 • Thermal Physics

KCSE 2025 Physics P1 Q14 — Crawling under smoke

Why are you told to crawl to the exit in a smoke-filled room? It comes down to the density of hot smoke versus cool air.

KCSE 2025 Physics Paper 1 Question 17 — a pendulum bob moving in a circle, with angular displacement, centripetal acceleration and centripetal force.
Physics • Form 4 • Forces

KCSE 2025 Physics P1 Q17 — Circular Motion

Define angular displacement, derive v = rω, and calculate the centripetal acceleration and force on a swinging pendulum bob.

KCSE 2025 Physics Paper 1 Question 16 — verifying Boyle's law, comparing diffusion of two gases, and applying Charles's law to a heated gas.
Physics • Form 4 • Thermal Physics

KCSE 2025 Physics P1 Q16 — Gas Laws

Verify Boyle's law, compare the diffusion of two gases, and use Charles's law to find the new volume of a heated gas.

KCSE 2025 Physics Paper 1 Question 19 — a stone and paper falling together in a vacuum, a car braking to rest, and a palm used to estimate the length of a table.
Physics • Form 4 • Forces

KCSE 2025 Physics P1 Q19 — Momentum & Free Fall

Explain free fall in a vacuum, find the change in momentum and stopping time of a braking car, and estimate a table's length using a palm.

KCSE 2025 Physics Paper 1 Question 18 — a metal block lowered into a measuring cylinder and weighed on a spring balance to verify Archimedes' principle.
Physics • Form 4 • Fluids

KCSE 2025 Physics P1 Q18 — Archimedes' Principle

State Archimedes' principle, measure the mass of water displaced, and verify that upthrust equals the weight of fluid displaced.

KCSE 2025 Physics Paper 1 Question 2 — a student and a tree casting shadows in the same sunlight, forming two similar triangles.
Physics • Form 4 • Measurement

KCSE 2025 Physics P1 Q2 — Tree Height by Shadows

Estimate the height of a tree from a student's height using shadows and similar triangles.

KCSE 2025 Physics Paper 1 Question 3 — a heavy block resting on the middle of a plank supported by two pivots, causing the plank to sag.
Physics • Form 4 • Forces

KCSE 2025 Physics P1 Q3 — Tension in a Plank

A block on a plank makes it sag — show how the tensional force acts on the plank.

KCSE 2025 Physics Paper 1 Question 4 — a tube of toothpaste being squeezed so paste flows out of the open nozzle.
Physics • Form 4 • Fluids

KCSE 2025 Physics P1 Q4 — Pascal's Principle

Why does toothpaste flow out when you squeeze the tube? Name and explain the principle.

KCSE 2025 Physics Paper 1 Question 6 — a clinical thermometer with a narrow constriction just above the mercury bulb.
Physics • Form 4 • Thermal Physics

KCSE 2025 Physics P1 Q6 — Thermometer Constriction

Why does a clinical thermometer keep its reading after it leaves the patient? Meet the constriction.

KCSE 2025 Physics Paper 1 Question 8 — an oval ball balanced upright on its narrow end on the ground.
Physics • Form 4 • Forces

KCSE 2025 Physics P1 Q8 — Unstable Equilibrium

Why is an oval ball balanced on its end unstable? Follow its centre of gravity.

KCSE 2025 Physics Paper 1 Question 5 — salt dissolving in water, with salt particles slotting into the gaps between water molecules.
Physics • Form 4 • Matter

KCSE 2025 Physics P1 Q5 — Shrinking Solution Volume

Salt plus water gives less volume than the sum of the two — explain why using particles.

KCSE 2025 Physics Paper 1 Question 7 — two spanners loosening the same nut, one with a short handle and one with a longer handle.
Physics • Form 4 • Forces

KCSE 2025 Physics P1 Q7 — Moments & Spanners

Two spanners, one nut — why does the longer one need less force? It's all in the moment.

KCSE 2025 Physics Paper 1 Question 9 — a spring hanging with known masses attached, being marked into a calibrated scale.
Physics • Form 4 • Measurement

KCSE 2025 Physics P1 Q9 — Calibrating a Spring

You have a spring and known masses — what else do you need to calibrate a spring balance?

Video thumbnail showing a grouped frequency table of the ages of 32 elderly residents, labelled KCSE 2025 Maths Paper 2 Question 10 Upper Quartile.
Mathematics • Form 4 • Statistics

KCSE 2025 P2 Q10 — Upper Quartile

Cumulative frequency, the Q3 position, and the grouped-data quartile formula.

Video thumbnail showing the first three terms of an arithmetic progression 8 minus x, 2x and 3x plus 2, labelled KCSE 2025 Maths Paper 2 Question 1 Arithmetic Progression.
Mathematics • Form 4 • Sequences & Series

KCSE 2025 P2 Q1 — Arithmetic Progression

Using the constant common difference of an AP to find x, then the difference itself.

Video thumbnail showing a circle on a Cartesian plane with centre (-2, 3) and radius 5, labelled KCSE 2025 Maths Paper 2 Question 11 Equation of a Circle.
Mathematics • Form 4 • Coordinate Geometry

KCSE 2025 P2 Q11 — Equation of a Circle

Building the circle equation from centre and radius, then finding where it crosses the x-axis.

Video thumbnail showing the compound interest formula with a Ksh 20,000 deposit at 2.5 percent every six months, labelled KCSE 2025 Maths Paper 2 Question 12 Compound Interest.
Mathematics • Form 4 • Commercial Arithmetic

KCSE 2025 P2 Q12 — Compound Interest

Compound interest, finding the number of periods with logarithms, then converting to years.

Video thumbnail showing three collinear points A, B and C on a straight line, labelled KCSE 2025 Maths Paper 2 Question 13 Ratio Dividing a Line.
Mathematics • Form 4 • Coordinate Geometry

KCSE 2025 P2 Q13 — Ratio Dividing a Line

Using vectors AB and AC to find the ratio in which B divides the line AC.

Video thumbnail showing a 2 by 2 transformation matrix and two triangles of different areas, labelled KCSE 2025 Maths Paper 2 Question 14 Matrix and Area Scale Factor.
Mathematics • Form 4 • Matrices & Transformations

KCSE 2025 P2 Q14 — Matrix & Area Scale Factor

Using the determinant as area scale factor to find the possible values of a.

Video thumbnail showing a particle moving along a straight line with velocity v = 4 - t, labelled KCSE 2025 Maths Paper 2 Question 15 Kinematics Integration.
Mathematics • Form 4 • Calculus

KCSE 2025 P2 Q15 — Kinematics (Integration)

Integrating velocity to find distance, using a known point to fix the constant.

Video thumbnail showing a sine wave oscillating between y = 2 and y = -2 with peaks marked, labelled KCSE 2025 Maths Paper 2 Question 16 Trigonometric Graph.
Mathematics • Form 4 • Trigonometry

KCSE 2025 P2 Q16 — Trigonometric Graph

Reading the amplitude and period off a sine graph to find the scalars A and omega.

Video thumbnail showing two heaps of groundnuts with prices Ksh 130 and Ksh 180 per kg, labelled KCSE 2025 Maths Paper 2 Question 17 Mixtures Profit and Ratio.
Mathematics • Form 4 • Commercial Arithmetic

KCSE 2025 P2 Q17 — Mixtures, Profit & Ratio

Cost price of a groundnut mixture, the percentage profit on selling it, and the mixing ratio.

Video thumbnail showing a monthly income tax band table and Judy's payslip, labelled KCSE 2025 Maths Paper 2 Question 19 Income Tax PAYE.
Mathematics • Form 4 • Commercial Arithmetic

KCSE 2025 P2 Q19 — Income Tax (PAYE)

Taxable income, PAYE band by band with relief, then working backwards to a new basic salary.

Video thumbnail showing music and mathematics club registration fees Ksh 7000 and Ksh 7200 with members switching, labelled KCSE 2025 Maths Paper 2 Question 18 Rational Equation.
Mathematics • Form 4 • Algebra

KCSE 2025 P2 Q18 — Rational Equation

Forming a rational equation from club fees, solving the quadratic for x, and a percentage increase.

Video thumbnail showing two thermometer readings of 20 and 25 degrees Celsius, labelled KCSE 2025 Maths Paper 2 Question 2 Maximum Possible Error.
Mathematics • Form 4 • Approximations & Errors

KCSE 2025 P2 Q2 — Maximum Possible Error

Why errors add when you subtract two measured quantities, giving a maximum error of 1 degree.

Video thumbnail showing a cubic curve with a straight line drawn across it and a table of x and y values, labelled KCSE 2025 Maths Paper 2 Question 20 Cubic Graph.
Mathematics • Form 4 • Graphs

KCSE 2025 P2 Q20 — Cubic Graph

Complete the cubic table, plot the curve, read the roots, then draw a line to solve a second cubic.

Video thumbnail showing a five-by-five probability grid and a probability tree for green and red balls, labelled KCSE 2025 Maths Paper 2 Question 22 Probability.
Mathematics • Form 4 • Probability

KCSE 2025 P2 Q22 — Probability

Probability space, both numbers greater than 3, sum not exceeding 6, then same-colour and mixed-colour draws.

Video thumbnail showing a labelled cuboid PQRSTUVW with midpoints M and N on the top edges, labelled KCSE 2025 Maths Paper 2 Question 21 3D Geometry.
Mathematics • Form 4 • Geometry

KCSE 2025 P2 Q21 — 3D Geometry (Cuboid)

Length RM in a cuboid, then the angle to the base, between two lines, and the obtuse angle between two planes.

Video thumbnail showing triangle ABC and its images on a grid with two transformation matrices, labelled KCSE 2025 Maths Paper 2 Question 23 Matrix Transformations.
Mathematics • Form 4 • Matrices & Transformations

KCSE 2025 P2 Q23 — Matrix Transformations

Image under T1, describing the stretch, the single combined matrix, then area by determinant scale factor.

Video thumbnail showing the surd expression 7 root 2 over 5 minus 3 root 2, labelled KCSE 2025 Maths Paper 2 Question 3 Rationalising Surds.
Mathematics • Form 4 • Surds

KCSE 2025 P2 Q3 — Rationalising Surds

Rationalising a surd denominator with its conjugate to read off a and b.

Video thumbnail showing the curve y equals x squared minus 4x plus 3 with a shaded region bounded by the line y equals 3 and x equals 3, labelled KCSE 2025 Maths Paper 2 Question 24 Area Under a Curve.
Mathematics • Form 4 • Calculus

KCSE 2025 P2 Q24 — Area Under a Curve

Definite integral, area above the axis by rectangle minus curve, area below, then the whole shaded region.

Video thumbnail showing the direct variation equation y equals k times (x plus 1) squared, labelled KCSE 2025 Maths Paper 2 Question 6 Direct Variation.
Mathematics • Form 4 • Variation

KCSE 2025 P2 Q6 — Direct Variation

y varies directly as the square of (x+1): find k and the connecting equation.

Video thumbnail showing an isosceles triangle MLN with M and N on the base, apex L at top, a 5 cm height, and a yellow arc through M, L and N marking the locus of P, labelled KCSE 2025 Maths Paper 2 Question 7 Loci and Construction.
Mathematics • Form 4 • Geometry

KCSE 2025 P2 Q7 — Loci & Construction

Constructing the 50-degree angle locus as a circular arc, then locating Q at half the triangle's area.

Video thumbnail showing the binomial expansion of (2 + 1 over 2x) to the power five, labelled KCSE 2025 Maths Paper 2 Question 4 Binomial Expansion.
Mathematics • Form 4 • Binomial Expansion

KCSE 2025 P2 Q4 — Binomial Expansion

Expand (2 + 1/2x) to the power 5, then estimate 2.05^5 from the first four terms.

Video thumbnail showing a circle with centre O, points A, B, C, D on the circumference and tangent FE at C, labelled KCSE 2025 Maths Paper 2 Question 5 Circle Tangent and Angles.
Mathematics • Form 4 • Geometry

KCSE 2025 P2 Q5 — Circle: Tangent & Angles

Alternate segment theorem plus angle at centre to find the acute angle BOC.

Video thumbnail showing the equator with point T at longitude 50 degrees west and point U reached by travelling 9000 nautical miles due east, labelled KCSE 2025 Maths Paper 2 Question 8 Longitude and Nautical Miles.
Mathematics • Form 4 • Latitude & Longitude

KCSE 2025 P2 Q8 — Longitude & Nautical Miles

Converting 9000 nautical miles along the equator into degrees of longitude to find point U.

Video thumbnail showing a displacement-time curve rising from 6 m to a peak near 7.4 m then falling to zero at t = 1 s, with a tangent drawn at t = 0.5 s, labelled KCSE 2025 Maths Paper 2 Question 9 Rate of Change from a Graph.
Mathematics • Form 4 • Calculus

KCSE 2025 P2 Q9 — Rate of Change from a Graph

Drawing a tangent to a displacement-time curve at t = 0.5 s and reading its gradient as the velocity.

Number cards 2, 4, 5 and 9 with a question asking which set holds prime numbers only.
Mathematics • Grade 9 • Numbers

KJSEA 2025 Maths Q1: Prime Numbers

Which set has prime numbers only? Test 2, 4, 5 and 9 with the two-factor rule.

Thumbnail showing a cylindrical bucket of water with the surface area of a cylinder formula for KJSEA 2025 Maths Question 10.
Mathematics • Grade 9 • Measurement

KJSEA 2025 Maths Q10 — Cylinder Surface Area

Find the bucket surface touching the water: circular base plus curved wall, top left out.

Thumbnail showing a cuboid milk packet with dimensions and the KJSEA 2025 Maths Q11 capacity question
Mathematics • Grade 9 • Measurement

KJSEA 2025 Q11 — Capacity

Find the capacity of a cuboid milk packet in litres.

Video thumbnail showing the Kelvin to Celsius conversion for KJSEA 2025 Maths Question 12.
Mathematics • Grade 9 • Measurement

KJSEA 2025 Q12 — Kelvin to Celsius

Choose the calculation that converts a Kelvin reading to degrees Celsius.

Thumbnail showing a window with an estimated height of 1.5 m and an actual height of 1.2 m, with the percentage error calculation 0.3 over 1.2 times 100.
Mathematics • Grade 9 • Measurement

KJSEA 2025 Maths Q14 — Percentage Error

Which calculation gives the percentage error when an estimate of 1.5 m misses the actual 1.2 m?

Video thumbnail showing a mobile money charges table with the question about how much Loymer remained with after sending and withdrawing money.
Mathematics • Grade 9 • Numbers

Q13 — Mobile Money Charges

Work out the balance left after sending and withdrawing money plus charges.

Video thumbnail showing an architectural wall drawing with the scale 1 to 100 and Q16 Scale Drawing title.
Mathematics • Grade 9 • Measurement

Q16 Scale Drawing

Use a 1:100 scale to find how long a 3 m wall is on the drawing.

Video thumbnail showing a rhombus with its diagonals crossing at right angles, labelled KJSEA 2025 Maths Question 15.
Mathematics • Grade 9 • Geometry

KJSEA 2025 Maths Q15 — Quadrilaterals

Which quadrilateral has diagonals that bisect each other at 90 degrees? It's the rhombus.

Thumbnail showing an original 16 cm photograph and its enlarged copy that is twice as long, with the enlargement calculation.
Mathematics • Grade 9 • Geometry

KJSEA 2025 Q18 — Enlargement

Enlarge a 16 cm photograph by a scale factor of 2 to find its new length.

Thumbnail showing the line equation 2y = x + 3 with the question 'gradient of the perpendicular line L2?' for KJSEA 2025 Maths Q17.
Mathematics • Grade 9 • Geometry

KJSEA 2025 Maths Q17 — Perpendicular Gradient

Find the gradient of a line perpendicular to 2y = x + 3 using the negative reciprocal rule.

Thumbnail showing 11 lettered cards with the three E cards highlighted and the fraction 3/11 for KJSEA 2025 Maths Question 20.
Mathematics • Grade 9 • Statistics

KJSEA 2025 Maths Q20 — Probability

Find the probability of drawing a card marked E from 11 lettered cards.

Thumbnail showing KJSEA 2025 Grade 9 Maths Question 2 on finding the HCF of 120, 180 and 24
Mathematics • Grade 9 • Numbers

KJSEA 2025 Maths Q2 — HCF

Find the largest number of equal groups by taking the HCF of 120, 180 and 24.

Thumbnail showing KJSEA 2025 Grade 9 Maths Question 21 on place value and rounding a distance in a 10,000 metre race.
Mathematics • Grade 9 • Numbers

KJSEA 2025 Maths Q21 — Place Value & Rounding

Subtraction, number words and rounding 6,784 to the nearest 100.

Video thumbnail showing KJSEA 2025 Grade 9 Maths Question 23 on ratio, with the ratio 5:7:3 and 60 children.
Mathematics • Grade 9 • Numbers

KJSEA 2025 Maths Q23 — Ratio

Sharing a Thanksgiving crowd in the ratio 5:7:3 to find men, women, and the difference.

Thumbnail showing a large metallic cube container with the question 'How many small cubes fit inside?' and KJSEA 2025 Maths Q22.
Mathematics • Grade 9 • Measurement

KJSEA 2025 Maths Q22 — Volume & Packing

Find a cube's volume, then count how many small cubes fit inside.

Video thumbnail showing KJSEA 2025 Grade 9 Maths Question 27 on matrices, with two 2 by 3 fruit-purchase matrices being added.
Mathematics • Grade 9 • Algebra

KJSEA 2025 Maths Q27 — Matrices

Form two 2 by 3 matrices for weekly fruit buys, then add them to get each family's totals.

Video thumbnail showing a KJSEA 2025 Grade 9 Maths work-rate question about men, hours and days packing flour.
Mathematics • Grade 9 • Numbers

KJSEA 2025 Maths Q24 — Work Rate

Solve a work-rate problem using man-hours to find how many extra days are needed.

Video thumbnail showing the recurring decimal 0.17 being converted step by step into the fraction 8 over 45.
Mathematics • Grade 9 • Numbers

Q25 — Recurring Decimal to Fraction

Turn 0.17 recurring into a fraction using the multiply-and-subtract trick.

Thumbnail showing KJSEA 2025 Maths Question 26 on simultaneous equations for books and pens with worked elimination steps.
Mathematics • Grade 9 • Algebra

KJSEA 2025 Maths Q26 — Simultaneous Equations

Solve two simultaneous equations by elimination to find the cost of a book and a pen.

Diagram of a solid cone with slant height 20 cm and base radius 4.2 cm, titled KJSEA 2025 Maths Q29.
Mathematics • Grade 9 • Measurement

KJSEA 2025 Maths Q29 — Surface Area of a Cone

Find the total surface area of a solid cone with slant height 20 cm and radius 4.2 cm.

Thumbnail showing a straight line on a coordinate grid passing through the point (1, 4) with its equation and x-intercept.
Mathematics • Grade 9 • Geometry

Q28 — Equation of a Line

Point-gradient form to find a line through (1, 4), then solve for the x-intercept.

Video thumbnail showing a number line with an arrow moving from -8 to +7 for a KJSEA 2025 integers question.
Mathematics • Grade 9 • Numbers

KJSEA 2025 Maths Q3 — Integers

Add a positive integer to a negative one to find a new temperature.

Thumbnail showing a cylindrical tin of water with a spherical ball being lowered in, and the label Q30 Volume and Displacement.
Mathematics • Grade 9 • Measurement

KJSEA 2025 Maths Q30 — Volume & Displacement

A ball sinks in a tin — find how much the water rises using displacement.

Thumbnail showing a metal rod leaning against a wall forming a right-angled triangle, with Pythagoras and density formulas.
Mathematics • Grade 9 • Measurement

KJSEA 2025 Maths Q31: Pythagoras & Density

Find a leaning rod's length with Pythagoras, then work out density from mass and volume.

Video thumbnail showing a globe with longitude lines and clocks marking the time at towns P and Q for KJSEA 2025 Maths Q32.
Mathematics • Grade 9 • Measurement

KJSEA 2025 Q32 — Longitude & Time

Use the longitude difference between two towns to work out the local time at town P.

Ruler-and-compasses construction of parallelogram ABCD with a 45 degree angle at A and a perpendicular dropped from D to AB at E.
Mathematics • Grade 9 • Geometry

KJSEA 2025 Maths Q34 — Parallelogram Construction

Construct parallelogram ABCD, drop a perpendicular from D to AB, and measure DE.

Video thumbnail showing KJSEA 2025 Grade 9 Maths Question 33 on import duty, excise duty and VAT for an imported printing machine.
Mathematics • Grade 9 • Numbers

KJSEA 2025 Q33 — Import Duty, Excise & VAT

Work out import duty, excise duty and VAT as percentages of a Ksh 1.2 million customs value.

Thumbnail showing a linear graph rising from the origin with the equation y = 50x for milk sales
Mathematics • Grade 9 • Algebra

Q35 — Linear Graphs

Complete the table for y = 50x and draw the milk-earnings line.

Diagram of a building with a person on a balcony looking down at a ball 47 m away, showing a 35 degree angle of depression
Mathematics • Grade 9 • Trigonometry

KJSEA 2025 Maths Q36 — Angle of Depression

Find the height of Dowdy's balcony using a 35° angle of depression and the tangent ratio.

Scale drawing showing a route from A to B to C with north lines and bearings, and the line AC measured for distance and bearing
Mathematics • Grade 9 • Geometry

KJSEA 2025 Maths Q37 — Bearings

Draw the two legs to scale, join A to C, then measure to get 86 m on a bearing of 174°.

Thumbnail showing a cuboid unfolded into a flat net with the label Q38 Net and Surface Area, KJSEA 2025 Grade 9 Maths.
Mathematics • Grade 9 • Measurement

KJSEA 2025 Q38 — Cuboid Net & Surface Area

Draw the net of a 5 by 3 by 2 cm cuboid and add all six faces to get 62 cm squared.

Video thumbnail showing KJSEA 2025 Grade 9 Maths Question 39 on statistics, with a frequency table and the mean and median calculations.
Mathematics • Grade 9 • Statistics

KJSEA 2025 Maths Q39 — Mean & Median

Tally 20 test marks into a frequency table, then calculate the mean and median.

Video thumbnail showing KJSEA 2025 Grade 9 Maths Question 4 on fractions of time, with the calculation for extra time planting seedlings.
Mathematics • Grade 9 • Numbers

KJSEA 2025 Maths Q4 — Fractions of Time

Which calculation gives the extra time used planting 70 seedlings? A clear fractions-of-time walkthrough.

Thumbnail showing a flash card with the index equation 2 to the power X times 2 cubed equals 32, labelled KJSEA 2025 Maths Q5 Indices.
Mathematics • Grade 9 • Numbers

KJSEA 2025 Maths Q5 — Indices

Use the laws of indices to solve 2^X × 2^3 = 32 and find X.

Number line for KJSEA 2025 Maths Q7 with a solid dot at 30 and an open circle at 50
Mathematics • Grade 9 • Algebra

KJSEA 2025 Maths Q7 — Inequalities

Turn 'at least 30 but fewer than 50 learners' into a compound inequality and graph it.

Thumbnail showing a coin and a die with a grid of all possible outcomes for KJSEA 2025 Maths Question 40.
Mathematics • Grade 9 • Statistics

KJSEA 2025 Maths Q40 — Probability Space

List all 12 outcomes of tossing a coin and a die, then find the probability of a head and a four.

Thumbnail showing KJSEA 2025 Grade 9 Maths Question 6 on algebraic expressions, with a farm animals word problem.
Mathematics • Grade 9 • Algebra

KJSEA 2025 Q6 — Algebraic Expressions

Write an algebraic expression for the number of sheep on a 26-animal farm.

Video thumbnail showing a football results matrix with the question asking for the order of the matrix.
Mathematics • Grade 9 • Algebra

KJSEA 2025 Maths Q8 — Order of a Matrix

Count the rows and columns to state a matrix's order — worked step by step.

Video thumbnail showing two algebraic fractions being added and simplified on a whiteboard for Alliance Form 3 Paper 1 Question 11.
Mathematics • Form 3 • Algebra

Alliance F3 P1 Q11 — Algebraic Fractions

Add two algebraic fractions and simplify by finding the common denominator.

Video thumbnail showing a thin square brass plate with the density, mass and volume formula for finding its side length.
Mathematics • Form 3 • Measurement

Density: Length of a Brass Plate

Use density, mass and thickness to find the side length of a thin square brass plate.

Video thumbnail showing a slow clock time problem for Alliance Form 3 Paper 1 Question 12
Mathematics • Form 3 • Measurement

Q12 Time — A Slow Clock

A clock loses 15 seconds every hour — find what it shows after 60 hours.

Thumbnail showing a cube with one square face highlighted and its corner-to-corner diagonal drawn in
Mathematics • Form 3 • Measurement

Diagonal of a Cube Face

Use the volume to find the edge, then Pythagoras for the face diagonal.

Video thumbnail showing a BODMAS fraction expression being evaluated step by step, with the word BODMAS highlighted.
Mathematics • Form 3 • Numbers

Form 3 P1 Q1 — BODMAS Evaluation

Use BODMAS to evaluate a signed-number fraction and get -2.

Thumbnail showing position vectors OA and OB plotted on a grid with the arrow AB and the label Q15 Vectors Magnitude.
Mathematics • Form 3 • Geometry

Vectors: Magnitude of AB

Find AB from OA and OB, then use Pythagoras to get its length to one decimal place.

Video thumbnail showing a compound linear inequality being solved and graphed on a number line.
Mathematics • Form 3 • Algebra

Form 3 P1 Q14 — Linear Inequalities

Split a compound inequality into two parts, solve each, and graph the solution on a number line.

Video thumbnail showing Alliance Form 3 Paper 1 Question 17 on ratio and profit, featuring a farmer's maize bags and lorry transport.
Mathematics • Form 3 • Numbers

Ratio, Trips & Profit — Q17

A three-part ratio and profit problem: mass lost after drying, number of lorry trips, and the selling price for a 26% profit.

Video thumbnail showing a rectangular floor being covered with square tiles and a shilling cost calculation for Alliance Form 3 Paper 1 Question 18.
Mathematics • Form 3 • Measurement

Alliance F3 P1 Q18 — Tiles & Profit

Count the tiles for a floor, cost 15 rooms, then price each carton for a 12.5% profit.

Thumbnail showing three bells with intervals 9, 15 and 21 minutes and the LCM time calculation
Mathematics • Form 3 • Numbers

Form 3 P1 Q2 — Bells & LCM

Three bells and their LCM tell you exactly when they last chimed together.

A coordinate grid showing a small square ABCD being enlarged, reflected and rotated into new positions.
Mathematics • Form 3 • Geometry

Form 3 P1 Q21 — Combined Transformations

Enlarge, reflect and rotate a square, then name the single transformation that links the two images.

Scale drawing of points P, Q, R and S with north lines and bearings marked, showing the ranch split into two triangles.
Mathematics • Form 3 • Geometry

Form 3 P1 Q19 — Bearings & Scale Drawing

Bearings, right-angle trig and Pythagoras to find PS, a bearing and the ranch area.

Thumbnail showing a coordinate grid with three straight lines labelled L, P and Q and the question number 20.
Mathematics • Form 3 • Geometry

Coordinate Geometry: Lines L, P & Q

Find the equations of three related lines and the point where the perpendicular meets the parallel line.

Cross-section diagram of a large cone with a smaller similar cone scooped out of its base, forming a conical hole.
Mathematics • Form 3 • Measurement

Cone with a Conical Hole

Use similar cones to find the hole radius, volume removed and total remaining surface area.

A speed–time graph of a cheetah rising from 15 m/s to a maximum, holding steady, then falling to zero at 40 seconds.
Mathematics • Form 3 • Measurement

Speed–Time Graph (Cheetah)

Read a cheetah's speed–time graph to find its top speed, accelerations and average speed.

Video thumbnail for Alliance Form 3 Paper 1 Question 24 on commission and percentages.
Mathematics • Form 3 • Numbers

Q24 — Commission & Percentages

Find monthly earnings from commission plus salary, then reverse the process to get total sales and units sold.

Video thumbnail showing a currency exchange question converting US dollars to Kenya shillings and then to British pounds.
Mathematics • Form 3 • Numbers

Currency Exchange: Buying vs Selling Rates

Convert $100,000 to shillings then to pounds using the correct bank rates.

Video thumbnail showing a KCSE simultaneous equations word problem about the cost of hiring technicians and artisans.
Mathematics • Form 3 • Algebra

Form 3 P1 Q3 — Simultaneous Equations

Turn a hiring word problem into two equations and solve by elimination.

Thumbnail showing a regular polygon with one interior angle labelled 3x and its exterior angle labelled x minus 20.
Mathematics • Form 3 • Geometry

Alliance F3 P1 Q5 — Angles of a Regular Polygon

Use angles on a straight line and the exterior-angle sum to find how many sides the polygon has.

Video thumbnail showing an index expression with fractional powers of 243, 125 and 9 being simplified to 75.
Mathematics • Form 3 • Algebra

Alliance F3 P1 Q6 — Laws of Indices

Simplify a fractional-power expression using the laws of indices — step by step to 75.

Video thumbnail showing the trigonometry equation sin(x+60) = cos 2x for Alliance Form 3 Paper 1 Question 8.
Mathematics • Form 3 • Trigonometry

Complementary Angles: Solving for tan(x+60)

Use the sine-cosine complementary rule to solve sin(x+60)=cos 2x, then find tan 70 degrees.

Thumbnail showing a closed cylinder with its radius equal to its height and the total surface area labelled 154 square centimetres.
Mathematics • Form 3 • Measurement

Cylinder Surface Area: Find the Diameter

Radius equals height and total surface area is 154 cm² — find the diameter to 2 d.p.

Ruler-and-compass construction of triangle ABC with AB 5 cm, a 120 degree angle at A, and BC 10 cm, with angle ABC marked.
Mathematics • Form 4 • Geometry

Triangle Construction (Q10)

Construct triangle ABC and measure angle ABC, confirmed by the sine rule.

Thumbnail showing a square-root surd expression being evaluated step by step for KCSE 2025 Maths Paper 1 Question 1.
Mathematics • Form 4 • Numbers

KCSE 2025 Maths P1 Q1 — Order of Operations

Use BODMAS and fraction skills to evaluate a square-root expression by hand.

Thumbnail showing KCSE 2025 Maths Paper 1 Question 11 on profit and loss, solving for the cost price of an item.
Mathematics • Form 4 • Numbers

KCSE 2025 P1 Q11 — Profit & Loss

Set up profit and loss equations, add them to eliminate the cost price, and find what the shopkeeper paid.

Thumbnail showing a histogram with three bars and the task to find missing frequencies for KCSE 2025 Maths Paper 1 Question 12.
Mathematics • Form 4 • Statistics

Histogram Frequencies (KCSE 2025 P1 Q12)

Find the two missing frequencies from histogram bar heights using frequency density.

Thumbnail showing a grid with triangle ABC, its reflected image points A dash and C dash, and a mirror line drawn between them.
Mathematics • Form 4 • Geometry

Reflection: Finding the Mirror Line

Use the perpendicular bisector to construct the mirror line and finish the reflected triangle.

Right-angled triangle ABC with point D on AC, showing AB = 8 cm, AD = 5 cm, and the area of triangle ABD marked as 10 square cm.
Mathematics • Form 4 • Trigonometry

KCSE 2025 Maths P1 Q15 — Trigonometry

Use a triangle's area to unlock a hidden angle, then find BC with tan.

Video thumbnail showing a trapezoidal prism being unfolded into its labelled net of four rectangles and two trapezium ends
Mathematics • Form 4 • Geometry

Net of a Prism

Unfold a trapezoidal prism into four rectangles and two trapezium ends to draw its labelled net.

Video thumbnail showing the curve y = 3x^2 - 4x with a tangent line drawn at point P(1, -1).
Mathematics • Form 4 • Calculus

Tangent to a Curve at a Point

Differentiate the curve, find the gradient at P, then form the tangent line.

Video thumbnail showing a lorry and a car travelling towards each other on a 160 km road, meeting at point C, for KCSE 2025 Maths Paper 1 Question 17.
Mathematics • Form 4 • Measurement

KCSE 2025 P1 Q17 — Speed, Distance & Time

Two vehicles meet on a 160 km road — find the meeting time, distance and the car's return speed.

Thumbnail showing a right pyramid mounted on a rectangular block with labelled dimensions for KCSE 2025 Maths Paper 1 Question 18.
Mathematics • Form 4 • Measurement

KCSE 2025 P1 Q18 — Volume & Surface Area

A right pyramid sits on a 6 by 6 by 10 block — find its volume, then the surface area of one cut half.

Thumbnail for KCSE 2025 Maths Paper 1 Question 2 on ratio, showing an hourly rate being changed in the ratio 8 to 7.
Mathematics • Form 4 • Numbers

KCSE 2025 Maths P1 Q2 — Ratio

Change an hourly rate in the ratio 8:7 and find the pay for 10½ hours.

Coordinate grid showing line L1 through points A and B, a parallel line L2, and a perpendicular line L3 meeting L2 at point P.
Mathematics • Form 4 • Geometry

KCSE 2025 P1 Q19 — Coordinate Geometry

Gradients, parallel and perpendicular line equations, and the intersection point P.

Video thumbnail showing KCSE 2025 Maths Paper 1 Question 20 on matrices, with the two lorry equations and the matrix solution.
Mathematics • Form 4 • Algebra

KCSE 2025 P1 Q20 — Matrices

Solve a sand transport problem using the matrix method and calculate the transporter's profit.

Video thumbnail showing a grid with points P and Q and the vector PQ drawn, labelled KCSE 2025 Maths Paper 1 Question 21 Vectors.
Mathematics • Form 4 • Geometry

KCSE 2025 P1 Q21 — Vectors

Column vector PQ, solving for scalars k and h, then the magnitude of ka.

Video thumbnail showing a constructed trapezium ABCD with an arc of centre A and radius 5 cm.
Mathematics • Form 4 • Geometry

KCSE 2025 P1 Q22 — Trapezium Construction

Construct trapezium ABCD, then work out the area lying outside the arc of centre A.

Thumbnail showing a frequency distribution table with the mean and median amounts spent on petrol highlighted.
Mathematics • Form 4 • Statistics

KCSE 2025 P1 Q23 — Mean & Median

Build a frequency table and estimate the mean and median money spent on petrol.

Diagram of an L-shaped plot of land ABCDEF with an added rectangle BCDG, forming a larger rectangle AGEF, on the video thumbnail.
Mathematics • Form 4 • Calculus

KCSE 2025 P1 Q24 — Maximum Area

Maximise the area of a plot of land using differentiation.

Thumbnail showing the double inequality with (5 - 2x)/3 and the label Q4 Inequalities KCSE 2025 Maths Paper 1.
Mathematics • Form 4 • Algebra

KCSE 2025 P1 Q4: Double Inequality

Split a double inequality into two parts, solve each, then combine to get 1 < x ≤ 4.

Thumbnail showing an indices equation with 4, 8 and 32 being rewritten as powers of 2 to solve for x.
Mathematics • Form 4 • Algebra

KCSE 2025 P1 Q3: Indices

Solve for x by rewriting every term as a power of 2, then comparing indices.

Thumbnail showing a rectangular farm on a grid with a dotted flooded section shaded blue
Mathematics • Form 4 • Measurement

Area by Counting Squares

Estimate the un-flooded area of a rectangular farm by counting grid squares.

Video thumbnail showing KCSE 2025 Maths Paper 1 Question 6 on finding the highest common factor of 240 and 150.
Mathematics • Form 4 • Numbers

KCSE 2025 P1 Q6 — Highest Common Factor

Find the least number of families by using the HCF of 240 kg and 150 kg.

Thumbnail showing a cone with base radius 7 cm, vertical height, and slant height, formed from a 550 square centimetre sector.
Mathematics • Form 4 • Measurement

Cone from a Sector

Roll a 550 cm² sector into a cone of radius 7 cm and find its height.

Thumbnail showing the algebraic fraction (x squared minus 4y squared) over (x squared plus 4xy plus 4y squared) being simplified.
Mathematics • Form 4 • Algebra

KCSE 2025 P1 Q7 — Algebraic Fractions

Factorise the top and bottom, cancel the common factor, and simplify the algebraic fraction.

Video thumbnail showing a wall clock with the KCSE 2025 Maths Paper 1 Question 9 label on time lost by a slow clock.
Mathematics • Form 4 • Measurement

KCSE 2025 P1 Q9 — Slow Clock

A clock loses 18 seconds an hour — what does it read on Saturday at 11:20 am?