Three chests—A, B, and C—contain coins. Chest A has twice as many coins as Chest B. Chest C has 5 fewer coins than Chest B. If the total number of coins across all three chests is 35, how many coins are in Chest A?
20 coins
Let B be the coins in Chest B. Chest A has 2B and Chest C has B - 5. The total equation is 2B + B + (B - 5) = 35, which simplifies to 4B - 5 = 35, so 4B = 40 and B = 10. Chest A has 2 * 10 = 20 coins.
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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