If you reverse the digits of my current age, you get the age of my grandfather. Subtracting my age from his yields a positive multiple of 9. Furthermore, the sum of our ages is 88. How old am I?
35
The digits must reverse and sum to 88. Possible pairs: 17/71 (sum 88, diff 54), 26/62 (sum 88, diff 36), 35/53 (sum 88, diff 18). Grandfather must be older than the grandchild, so 53 - 35 = 18, and grandfather is 53, grandchild is 35.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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