Ratio, proportion and percentages
Ratio, proportion and percentages

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Ratio, proportion and percentages

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?


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 Text kg pudding takes 5 hours.

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


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.


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