Expressing One NumberExpressing One NumberAs a Fraction of Another.As a Fraction of Another.

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Stage 4Stage 4Years 7 & 8Years 7 & 8

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Expressing one quantity as a fraction of another. (1/5)

When expressing one quantity as a fraction of another.

Write the question in the form ““What fraction is A of B?”What fraction is A of B?”

A A and B B must be in the same units.

Write as AABB

, then simplify.

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Examples (2/5)

What fraction of 12 is 7?

““What fraction is 7 of 12?”What fraction is 7 of 12?”

771212

What fraction is 12 of 48?

12124848

÷2÷2

÷2÷2

662424

÷2÷2

÷2÷2

331212

÷3÷3

÷3÷3

1144

(Equivalent Fractions)

== == ==

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Examples (3/5)

What fraction is 7cm of 9cm?

““What fraction is 7cm of 9cm?”What fraction is 7cm of 9cm?”

7799

What fraction is 90cm of 1m?

9090100100

÷1÷100

÷1÷100

991010

What fraction is 90cm of 100cm100cm ?

==

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Examples (4/5)

My petrol tank holds 60 litres of petrol.

If it has 35 litres in the tank, what fraction of the tank has petrol in it?

““What fraction is 35 litres of 60 What fraction is 35 litres of 60 litres?”litres?”35356060

÷5÷5

÷5÷5

771212

==

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Examples (5/5)

What fraction is ⅜ of 1⅝?

11⅝⅝

⅜ ⅜ ::13133 :3 :

331313