Primary 6 · Chapter 4

Primary 6 Algebra Question Types

Read what a letter represents, build an expression and solve for an unknown number. Write your own working before comparing it with the solution.

Self-paced lessons · Modelled on top school exam questions · No sign-up for the samples

The Algebra chapter

Watch · The introduction

Start with the first idea

Watch the explanation, then try a question for yourself.

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Try · Modelled on top school exam questions

Try three questions, from easier to harder

Try each question yourself first, then check your answer or compare it with the solution. These questions are written by Mathweave, not copied from school papers. No sign-up is needed.

Question 1 of 3

Write an expression

Try solving it yourself before opening the solution.

Subtract p from 20. Write your answer as an algebraic expression.

Try it yourself first. Then open the solution to compare your answer and working.

Show the step-by-step solution

start at 20
take p off it
20 - p

Ans: 20 - p

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Question 2 of 3

Put in the given number

Try solving it yourself before opening the solution.

Find the value of 6p + 9 when p = 7.

Show the step-by-step solution

6p + 9 = 6 × 7 + 9
value = 42 + 9
value = 51

Ans: 51

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Question 3 of 3

Simplify, then solve

Try solving it yourself before opening the solution.

Find the value m represents in 7m + 16 - 2m = 61.

Show the step-by-step solution

7m + 16 - 2m = 61
7m - 2m + 16 = 61
5m + 16 = 61
5m = 61 - 16
5m = 45
m = 9

Ans: 9

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Continue with the method you need

Follow a lesson link beside a question, or browse the chapter below.

See practice plans See how practice works

The chapter · Seven question types

Primary 6 algebra questions by question type

A linked row opens a published lesson with its own film. Explore the explanation and available practice on that page.

4.1A letter is a unit with a nameA letter is a unit with a name
4.2Collecting like termsCollecting like terms: the simplest form
4.3Putting the number back inPutting the number back in: substitution
4.4Build the expression from the tableBuild the expression from the table
4.5Solve for the variableSolve for the variable
4.6Algebra on a figureAlgebra on a figure
4.7Mixed practicePractice questions, each with its worked solution.

The order · Two groups

The order to learn them

What a letter is, and what you can do with one
4.1 to 4.3
The word problems the papers set
4.4 to 4.6

The number tells you where a question type sits in this chapter, not what your child needs to learn first. A child who has already met a type in school can practise it without working through the ones above it.

The papers · Modelled against top school papers

How Paper 1 and Paper 2 set these questions

The PSLE Maths format from 2026.

Paper 1 has 30 questions for 50 marks: 18 multiple-choice questions and 12 short-answer questions. Paper 2 has 15 questions for 50 marks: 5 short-answer questions and 10 structured or long-answer questions.

Source: SEAB examination syllabus, from 2026

Algebra appears in both papers and often combines with another topic.

Paper 1 includes the short items: a line to simplify, an expression to evaluate, a sentence to write as an expression. The longer items appear in Paper 2, and they are almost always an expression built from a table of daily amounts, a story where the letter has to be recovered from a total, or algebra printed on a labelled figure.

Many higher-mark Paper 2 questions combine topics.

Close to half of Paper 2 questions combine two or more topics, often algebra with average, a bar graph or percentage. Practice questions are not labelled by type, so children must choose the methods they need.

Everything here is modelled against top school papers. Those papers are never reproduced, and every question on this site is original.

Written working · Clear methods, line by line

How to set out the working clearly

These examples show Mathweave's clear, consistent layout for each method. The layout is informed by the answer keys we reviewed.

Write one chain with equals and collect on the same lineWrite the working as a single chain. The whole sum is written in the order the question gives it, and only then are the terms gathered. There is no preamble announcing the number represented by the letter, and no vertical stack of one term to a row.
The whole line is written again with the number in place of the letterBefore calculating, rewrite the full expression with the number in place of every occurrence of the letter. This reduces the risk of dropping a term. Some papers write 9(4) where the films write 9 times 4, and the two mean the same thing.
Solving is written as arithmetic, never as a balanceUndo the operations in reverse order. A short question may be solved with arithmetic alone. An equation is a more reliable method when the wording has several steps.
Put the unit outside brackets when the answer is an expressionWrite (n + 3) buns so the unit applies to the whole expression. Use the same form for a length or an amount of money.

Parents · Asked and answered

Questions parents ask

Is this the PSLE syllabus?

The question types follow the latest MOE Primary Mathematics syllabus. The syllabus's own word at this level is 'letter', not 'variable', so 'letter' is the word every film uses.

Has my child met any algebra before Primary 6?

Formal algebra begins in Primary 6. The chapter connects a letter for an unknown number with the familiar unit method used in ratio.

Are the questions from past papers?

We write the questions ourselves rather than copy them from papers. Each chapter is modelled on the types of question that top school papers set. A question may look like one your child has met before because it is the same type.

What does the practice add over the films?

Practice uses different numbers for each question type, points out the common mistake when your child makes it and records which types your child can complete independently.

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