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Weighing a Counterfeit Coin
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Weighing a Counterfeit Coin,
a selection of answers from the Dr. Math archives.
- Find the Heavier Coin of 12
in 3 Weighings
- If there are twelve coins in a bag, one of which is either lighter
or heavier than the others, find the fake coin in exactly 3 weighings
AND determine if it is lighter or heavier than the others.
- Finding the Counterfeit Coin
(1 of 9)
- One of nine coins is counterfeit and is lighter or heavier than the
others. How do I locate it in three weighings only?
- Finding One Coin of 12 in
- Given a pile of twelve coins of equal size with one of a different
weight, in three weighings find the unequal coin...
- 3 Weighings Problem
- You have a balance scale and 12 balls that all look and weigh the
same except one...
- Use One Weighing
- There are 90 genuine coins and 10 fake coins in 10 stacks with
10 coins in each stack... Using only one weighing, determine which
stack contains the fake coins.
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