I am thinking of a fraction. My numerator is increased by 4, and my denominator is 12. Simplified, I am equal to 1/2. What was my original numerator?
2
Let original numerator be x. (x + 4) / 12 = 1/2. Cross multiply: 2(x + 4) = 12 => 2x + 8 = 12 => 2x = 4 => x = 2.
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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