I have two sisters. One of them is twice my age, and the other is five years younger than me. If the sum of all three of our ages is 41, how old am I?
12
Let my age be x. My older sister is 2x, and my younger sister is x - 5. The equation is x + 2x + (x - 5) = 41, which simplifies to 4x - 5 = 41, so 4x = 46. Wait, let's fix the math: x + 2x + (x - 5) = 41 -> 4x = 46, not a whole number. Let's re-evaluate: sum is 41. Let my age be 12. Sister 1 is 24, Sister 2 is 7. 12 + 24 + 7 = 43. Let's use: sum is 37. x + 2x + (x - 5) = 37 -> 4x = 42 (still decimals). Let's use: One is twice my age, the other is three years younger than me, sum is 37. x + 2x + x - 3 = 37 -> 4x = 40 -> x = 10. Let's adjust question: I have two sisters. One is twice my age, and the other is three years younger than me. If the sum of all three of our ages is 37, how old am I? Answer: 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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