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Brothers and Sisters

Age 11 to 14 Short Challenge Level:


A boy has the same number of sisters as brothers.

Each of his sisters has only half as many sisters as brothers.

How many brothers and sisters are in the family altogether?




If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.


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