You have 12 balls, equally big, equally heavy - except for one. You only know that one ball is different.
How would you identify the heavier ball if you could use a pair of balance scales only three times? You need to find out if the ball is heavier or lighter
There is a solution!!. Is not one of those when at the end the guy tells you there is no solution..
Number the balls from 1 to 9. Weigh {1,2,3} against {4,5,6}. If one set is heavier, the heavier ball is among those three balls. If they're of equal weight, then the heavier ball is among {7,8,9}.
To find the heavier ball among, say, {1,2,3} only weighing once, we weigh {1} against {2}. If either one is heavier than the other, that one is the heavier ball. If they're of equal weight, {3} is the heavier ball.
For these problems, it helps to reason backwards. Start at the end: from how many balls can I discern the heavier one if I can weigh only once? Then extend to weighing twice, and so on.
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Come on u can do better!!!
To find the heavier ball among, say, {1,2,3} only weighing once, we weigh {1} against {2}. If either one is heavier than the other, that one is the heavier ball. If they're of equal weight, {3} is the heavier ball.
If either one is hevier than the other... (you dont know obviously here if one is heavier or the other one is lighter)
So you are very very wrong, but keep trying!
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Sorry I took the wrong one, you were right that one was very easy because it says one ball is havier. I change the game now for the dificult one. That is not that easy :)
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Nice @gargon
Shot you an Upvote :)
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Upvoted
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