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Shifting Average

Age 11 to 14 Short Challenge Level:


The average of four numbers is 48.

If 8 is subtracted from each number, what is the average of the four new numbers?



This problem is taken from the World Mathematics Championships
You can find more short problems, arranged by curriculum topic, in our short problems collection.
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.
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