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One quantity as a fraction of
another
2.9
This section will show you how to:
● express one quantity as a fraction of another
Key words
fraction
quantity
You may often be asked to give one amount or quantity as a fraction of another.
EXAMPLE 10
Write £5 as a fraction of £20.
es
5
1
As a fraction this is written ––
20 . This cancels to –
4.
So £5 is one-quarter of £20.
EXERCISE 2I
D
In each of the following, write the first quantity as a fraction of the second.
a
2 cm, 6 cm
b
4 kg, 20 kg
c
£8, £20
d
5 hours, 24 hours
e
12 days, 30 days
f
50p, £3
g
4 days, 2 weeks
h
40 minutes, 2 hours
In a form of 30 pupils, 18 are boys. What fraction of the form are boys?
During March, it rained on 12 days. For what fraction of the month did it rain?
Reka wins £120 in a competition and puts £50 into her bank account. What fraction of
her winnings does she keep to spend?
FM
Jon earns £90 and saves £30 of it.
Matt earns £100 and saves £35 of it.
Who is saving the greater proportion of their earnings?
AU
In two tests Isobel gets 13 out of 20 and 16 out of 25. Which is the better mark?
Explain your answer.
CORE
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