 To calculate a fraction of a number mentally. To find a fraction of a quantity. To choose a way of working out and give a reason why that method was chosen.

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To calculate a fraction of a number mentally. To find a fraction of a quantity. To choose a way of working out and give a reason why that method was chosen. Lesson Objectives:

Mental starter: Using a spreadsheet to find fractions of numbers.

To find a fraction of a quantity. To choose a way of working out and give a reason why that method was chosen. Lesson Objectives:

3 4 of £2 Example problem

3 4 of £2 Example problem denominator numerator quantity

3 4 of £2 Method 1 First of all divide the quantity by the denominator of the fraction: £2 divided by 4 = 50p Next, multiply your answer by the numerator: 50p x 3 = £1.50

3 4 of £2 Method 2 First, convert the fraction to a decimal: 3/4 = 3 divided by 4 = 0.75 Next, multiply your answer by the quantity: 0.75 x £2 = £1.50

Which method is better? Why? Is one method always better than the other?

On your white board solve these problems using both methods, discuss quietly with the person next to you which method you think is better. Be prepared to share what you’ve learnt. Work out: 1.3/4 of £202.2/3 of £180 3.3/4 of £284.2/5 of £50 5.4/5 of £606.3/8 of £80 7.5/8 of £808.4/7 of £490

To find a fraction of a quantity. To choose a way of working out and give a reason why that method was chosen. Lesson Objectives:

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