# There are 2187 balls, out of them 1 is heavy. Find out the heavy ball with minimum no. of attempts to weighed the balls?

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There are 2187 balls, out of them 1 is heavy. Find out the heavy ball with minimum no. of attempts to weighed the balls?
posted Jul 20, 2017

after 7 weighings

1.Devide the balls into 3 piles(729 balls) and weigh 2 piles, we can find the heavier pile.
2. Then devide the 729 balls into 3 piles(243 balls) and weigh 2 piles, we can find the heavier pile.
3. Then devide the 243 balls into 3 piles(81 balls) and weigh 2 piles, we can find the heavier pile.
4. Then devide the 81 balls into 3 piles(27 balls) and weigh 2 piles, we can find the heavier pile.
5. Then devide the 27 balls into 3 piles(9 balls) and weigh 2 piles, we can find the heavier pile.
6. Then devide the 9 balls into 3 piles(3 balls) and weigh 2 piles, we can find the heavier pile.
7. Weigh 2 balls of the 3 balls. We can find one hevier ball.

Excuse my poor English.

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