Percentage
Read a percentage as a count out of a hundred, then convert between fractions, decimals and percentages and apply one to a quantity.
Your child learns that percent means out of a hundred, and writes the same amount as a fraction, a decimal and a percentage. Your child then expresses a part of a whole as a percentage and finds a percentage of a quantity, naming the whole as 100% each time. The chapter ends with shopping and saving: a discount, then GST, and a year of interest. Read the study guide →
About this chapter
The order to learn them
Percent means out of a hundred
9.1 to 9.3
Read a share of 100, convert between its three forms, and write one quantity as a percentage of another.
Which amount is the 100%?
9.4 and 9.5
Name the whole before calculating. After a discount, the discounted price becomes the new 100% for GST.
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.
How the end-of-year papers set these questions
Percentage appears in every 2025 Primary 5 end-of-year paper.
Direct questions ask for a percentage of a quantity or for one quantity as a percentage of another. Longer questions use discount and GST. The syllabus also includes annual interest.
The whole may be stated, implied or changed.
A percentage only has a value after the whole is known. In a price question, the original price is 100% for the discount, and GST is calculated from the discounted price.
The papers use both fraction and 1% methods.
A familiar percentage may be simplified as a fraction of the whole. Other questions find 1% first and multiply to reach the percentage required.
Everything here is modelled against top school papers. Those papers are never reproduced, and every question on this site is original.
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 the part over the whole in that order Put both quantities in the same unit first. Then write the named part over the whole and multiply by 100%.
- Keep the value unchanged when converting its form A percentage is written over 100 before it is simplified as a fraction. A decimal becomes a percentage by multiplying by 100 and writing the percent sign.
- Name the 100% before finding a percentage of it Write the whole on its own line. Then use a fraction of the whole or find 1% and scale up.
- Give each price stage its own 100% line Apply the discount to the original price. Use the discounted price as the new 100% before calculating GST. Calculate annual interest from the amount and period named in the question.
Questions parents ask
Is this in the Primary 5 syllabus?
Yes. The question types follow the Percentage outcomes in the latest MOE Primary Mathematics syllabus.
Why do two lessons also appear under Primary 6?
Finding a percentage of a quantity and applying discount with GST are taught at Primary 5 and used again at Primary 6. Each has its own Primary 5 page in this chapter, and Primary 6 has its own pages for them.
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.
Which practice is available now?
Practice is ready for all five question types. Mixed practice across Decimals, Rate and Percentage is being built.
Primary 5 percentage word problems by question type
Primary 5 Percentage Study Guide
From a hundred square to a price tag: count out of 100, switch between fractions, decimals and percentages, then work discounts, GST and interest. Five tap-through steps and a short check.
Start hereOut of 100Three spellingsPart of a wholeOf a quantityDiscount and GSTOpen the study guide →