NRICH: Choir Boys

Can you work out how many members this choir has from these percentages?

Two schools share a choir.

Last year there were 30 more students from school B than students from school A in the choir.

This year the number of choir members has increased by 10%.
The number of members from school A has increased by 20%.
The number of members from school B has increased by 5%.

How many members does the choir have this year?

This problem is taken from the UKMT Mathematical Challenges.

You can find more short problems, arranged by curriculum topic, in our short problems collection.

Age 14 to 16

Algebra & Pre-Algebra, Linear Equations, Ratios, Rates & Percents
High School

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NRICH (University of Cambridge)

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