Ratio, proportion and percentages

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# 2.2.1 Try some yourself

## Activity 12

A recipe for four people calls for teaspoon of mustard powder. How much should you use for ten people?

### Answer

For one person you need    teaspoons.

For ten people you need    teaspoons.

So almost 2 teaspoons of mustard are needed.

## Activity 13

The length of time it takes to cook a Christmas pudding in a pressure cooker depends on the weight of the pudding. Kim has forgotten the time per pound but remembers that her kg pudding takes 5 hours.

How long will it take to cook a 2 kg pudding?

### Answer

If it takes 5 hours to cook kg then the time to cook 1 kg is 5 ÷ hours.

So a 2 kg pudding takes    hours (6 hours 40 mins), assuming that cooking time is proportional to weight.

MU120_4M3

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