Today’s problem — free all day, every step. Every day has one.
At the concert — how many girls
Q9 — At a concert there were 30% more women than men and 25% more boys than girls. There were 250 people, with as many males as females. How many girls?
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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. "As many males as females" means the two mixed bars are the same length, so the boxes they share cancel — and what is left over, 3 units = 1 part, is the exchange rate that turns the second ratio into the first.
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…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.
A PDF, and a note when new solutions go up.