Find a non-unit fraction of a quantity using mental and written calculation strategies | Maths

Starter quiz

The whole has been divided into how many equal parts?

'3' ✓
Tick the bar model that represents this equation 35 × $\frac{1}{7}$ = 5
Calculate: 150 ÷ 5 = ______

'30' ✓
Solve the equation: 650 × $\frac{1}{5}$ = ______

'130' ✓
Tick the equations that represent this problem. There are 32 children in the class. One-eighth of the children had packed lunch for their lunch.

32 × 8 =

8 × 32 =

32 × $\frac{1}{8}$ = ✓

32 ÷ 8 = ✓
There are 220 grams of chopped tomatoes in a tin. A recipe requires one quarter of a tin of chopped tomatoes. How many grams of chopped tomatoes is this? ______ g

'55' ✓

Exit quiz

Tick the equations that represent this image.

12 × 3 = 36

$\frac{3}{4}$ × 12 = 9 ✓

12 × $\frac{3}{4}$ = 9 ✓

12 ÷ 4 = 3 ✓
Solve $\frac{5}{8}$ × 16 = ______

'10' ✓
Solve $\frac{4}{6}$ × 54 = ______

'36' ✓
To find a fraction of an amount, you can:

Divide the whole by the numerator and multiply that by the denominator.

Multiply the whole by the denominator and then divide that by the numerator.

Divide the whole by the denominator and then multiply that by the numerator. ✓
The whole is 909 Find the value of five ninths of the whole.

'505' ✓
There are 36 bags of sweets to be handed out after school to the class for Laura’s birthday. Five sixths of the bags are handed out. How many bags does she have left?

'6' ✓

Worksheet

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Lesson Details

Key learning points

The whole has been divided into __ equal parts and there are __ in each part.
Use representations of sets of objects to divide them into equal parts.
Count how many objects are in the number of parts needed.

Common misconception

Pupils procedurally divide by the denominator and multiply by the numerator without an understanding for why they do this.

Take time to ensure pupils link how the fraction relates to the bar model. Using the sentence stem 'The whole has been divided into ___ equal parts, and we need ___ of them,' can help to make sense of the fraction in relation to the bar model.

Keywords

Denominator - The denominator is the bottom number of a fraction. It tells you how many equal parts the whole has been divided into.
Numerator - The numerator is the top number of a fraction. It tells you how many parts we have, or are needed.