Four brothers share a bag of marbles. Arthur takes 1/4 of them, Ben takes 1/3 of the remainder, and Charlie takes half of what is left after that. David gets the final 6 marbles. How many marbles were in the bag originally?
24
David gets 6 (which is half of what Charlie left, so Charlie left 12). Ben took 1/3 of remainder, leaving 2/3 which is 12, so before Ben there were 18. Arthur took 1/4, leaving 3/4 which is 18, so original total was 24.
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: Hard. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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