I have two sisters. Each sister has two brothers, and I am a boy. How many total children are in our family?
Five
There are three girls (the boy and his 'two sisters' share the same sisters) and two boys (the boy himself and his brother). Wait, let's trace carefully: If every sister has two brothers, that means there are two boys in the family total. Since the speaker is a boy, those two brothers are him and one other. Since each sister shares the same brothers, there must be 3 girls. 3 girls + 2 boys = 5 children.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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