A merchant has a barrel of oil. She sells half of it, then sells a third of what is left, and finally sells a quarter of the remainder. What fraction of the original barrel of oil remains?
1/4
Start with 1. Selling half leaves 1/2. Selling a third of that leaves 2/3 of 1/2 = 1/3. Selling a quarter of that leaves 3/4 of 1/3 = 1/4.
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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