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Question P6 The equal concept

836 students — who takes the bus

There are 836 students in a school. of the boys and of the girls take bus to school. The number of boys who do not take bus is twice the number of girls who do not take bus. How many girls do not take bus?

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About this method

The equal concept

The question tells you a part of one pile equals a part of another.

In this one. Make the two numerators the same, and the fraction equation turns into a ratio of the two wholes: 3/10 of boys = 3/12 of girls says one tenth of the boys equals one twelfth of the girls, so Boys : Girls = 10 : 12.

the two shaded parts are the same sizePile Aa third of APile Ba fifth of B

How to spot it

Two different groups each get their own fraction or percentage, and the question links them with 'the same as', 'twice as many as', or a shared cost across different units.

Common mistake

Children compare the two fractions without first relating them to a common whole. A smaller fraction of a larger group can be bigger than a larger fraction of a smaller group.

Practise a similar question

Challenging A charity fun fair had 370 visitors, made up of children and adults. 7/9 of the children and 7/10 of the adults bought a raffle ticket. The number of children who did not buy a raffle ticket is twice the number of adults…
All 5 with this pattern →
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