I have two sisters. One is twice my age, and the other is half my age. When our ages are added together, the sum is 35. How old am I?
10
Let your age be X. Your older sister is 2X, and your younger sister is X/2. The equation is X + 2X + X/2 = 35, which simplifies to 3.5X = 35, making X = 10.
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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