Number
Number forms the foundation of GCSE Maths. It covers integers, fractions, percentages, powers, accuracy and exact calculations. Mastering number skills makes every other topic easier.
💡 In this topic, you’ll build strong number skills that support every part of GCSE Maths.
You’ll learn how to:
- Work confidently with fractions, decimals and percentages
- Calculate with integers and decimals, and use factors and primes
- Use powers, roots and standard form
- Round accurately and calculate bounds
- Apply percentage change and compound growth
- Develop Higher skills with recurring decimals, surds and exact values
What you’ll learn in Number
Follow the lessons in order, or return to a topic you need to practise. Select a lesson to get started.
NUMBER FOUNDATIONS
1. Integers, Place Value and Ordering
Read whole numbers and decimals, use number lines, and compare and order positive and negative values.
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2. Calculating with Integers and Decimals
Calculate with integers and decimals, check answers with inverse operations, and use the correct order of operations.
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3. Factors, Multiples and Primes
Find factors and multiples, recognise prime numbers, and use divisibility rules in simple problems.
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4. Powers and Roots
Understand powers and roots, then build towards index laws and clearly labelled Higher extensions.
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5. Prime Factorisation, HCF and LCM
Use factor trees and prime factors to find the highest common factor and lowest common multiple.
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6. Systematic Listing and Counting
Organise lists, tables and trees so no outcome is missed or repeated, with a Higher counting extension.
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FRACTIONS AND ACCURACY
7. Fractions, Decimals & Percentages
Understand fractions, decimals and percentages, and convert between these different forms of the same value.
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8. Calculating with Fractions
Add, subtract, multiply and divide fractions, including improper fractions and mixed numbers.
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9. Rounding and Estimation
Round whole numbers and decimals, use significant figures, and estimate to check calculations.
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10. Standard Form
Write, compare and calculate with very large and very small numbers using powers of ten.
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PERCENTAGES AND CHANGE
11. Percentages of an Amount
Find percentages of amounts using familiar fractions, mental methods and decimal multipliers.
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12. Percentage Increase and Decrease
Find percentage increases, decreases and percentage change, including working backwards to find an original amount.
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13. Compound Interest and Growth
Use repeated multipliers for compound interest, growth and depreciation, then find the total change or work backwards.
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14. Bounds and Error Intervals
Use rounding and truncation to write error intervals, then progress to Higher calculations with bounds.
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HIGHER NUMBER
15. Recurring Decimals
Use algebra to convert recurring decimals into exact fractions, including repeating blocks and non-recurring prefixes.
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16. Surds and Exact Calculations
Simplify and calculate with surds, rationalise denominators, and keep root and π answers exact.
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