You have three identical-looking coins: two weigh 5 grams each and one weighs 6 grams. You place Coin 1 on the left side of a balance scale and Coin 2 on the right side. The scale remains perfectly balanced. Which coin is the heaviest?
Coin 3
Because Coin 1 and Coin 2 balanced each other perfectly, they must weigh the exact same amount (5 grams each). Therefore, the remaining unweighed coin (Coin 3) must be the 6-gram coin.
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: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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