Numbers, units and arithmetic
Numbers, units and arithmetic

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Numbers, units and arithmetic

3.13.1 Try some yourself

Activity 52

Evaluate each of the following.


Activity 53

Evaluate each of the following, giving each answer in its simplest form.


Activity 54

Explain how to multiply fractions, to somebody who does not know how to do it.


There are several ways of explaining this. For example:

‘To multiply two fractions, multiply the top two numbers together (the numerators) and multiply the bottom two numbers together (the denominators). To give the answer in its simplest form, check whether top and bottom numbers have a factor in common and, if so, divide through by it.’


‘To multiply two fractions by cancelling, find a number that goes into (divides) a number on the top and a number on the bottom i.e. cancel. Repeat this until there are no numbers left which will cancel with each other. Then multiply together the top two numbers (the numerators) and the bottom two numbers (the denominators). This fraction should be in its simplest form.’


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