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P6 The equal concept

Today’s problem — free all day, every step. Every day has one.

Training workshop — men and women who didn't attend

A company has 880 employees, made up of men and women. of the men and of the women attended a training workshop. The number of men who did not attend is three times the number of women who did not attend. How many women did not attend the workshop?

One step of the worked solution to Training workshop — men and women who didn't attend, drawn in pencil.
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The pattern behind it: The equal concept

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

In this one. Scale 1/6 to 3/18 so both non-attending fractions have the same numerator: matching numerators create equal-sized units, so the denominators reveal the ratio of the two whole groups.

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.

Try one like it

Challenging 370 visitors — who bought a raffle ticket 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 ti…
All 5 with this pattern →

The 33 problem patterns

All 33 patterns, one to a page — the 19 behind Primary 5 and 6 word problems, and the skills the younger years are built on. The bar model, how to spot it in the question, and the mistake children make. A booklet you can print. Free.

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