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One or Both

Age 14 to 16
ShortChallenge Level Yellow starYellow star
Secondary curriculum
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A maths exam contained only two questions. Every pupil correctly answered at least one of the questions. 

Question one was correctly answered by 70% of the pupils. Question two was correctly answered by 60% of them.

Nine pupils correctly answered both questions.

How many pupils took the exam?


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

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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