• Fractions
• Adding and subtracting within one whole
• Mastery PD Materials

## Adding and subtracting within one whole

Spine 3: Fractions – Topic 3.4

### Introduction

Learn to name and write unit fractions. Recognise and show unit fractions of areas, lengths and quantities. Relate numerators and denominators to parts and wholes; explore how the greater the denominators, the smaller the unit fraction.

### Teaching points

• Teaching point 1: When adding fractions with the same denominators, just add the numerators.

• Teaching point 2: When subtracting fractions with the same denominators, just subtract the numerators.

• Teaching point 3: Addition and subtraction of fractions are the inverse of each other, just as they are for whole numbers.

• Teaching point 4: To subtract from one whole, first convert the whole to a fraction where the denominator and numerator are the same.

• Primary
• KS2
• Year 3
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