I am a positive whole number. If you double me and then subtract 7, you get 15. What number am I?
11
Setting up the equation 2x - 7 = 15 gives 2x = 22, so x = 11.
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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