I have two sisters. Together, our ages multiply to 36 and add up to the number of fingers on a standard human hand, excluding thumbs. How old am I?
2
A standard hand excluding thumbs has 4 fingers. The sisters' ages must add up to 4 and multiply to 36. The only three positive whole numbers that multiply to 36 and add to 4 are 2, 2, and 9 (since 2+2=4 and 2x2x9=36). Therefore, all three sisters are 2, 2, and 9 years old.
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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