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You have a basket of 9 oranges, 8 of the oranges have the same weight and 1 is heavier than the others. All the oranges looks and feels the same. You have a scale but you are allowed to use it only 2 times. How could you find the heaviest orange?

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Split the nine oranges into

Three piles of three, piles A, B, and C.

Compare the weights of

Piles A and B. If they weigh the same, the heavy orange is in pile C. If either of those two piles are heavier, the heavy orange is in that pile.

Then, compare the weights of

Two of the oranges from the heavier pile. If they're the same, then the third orange is the heaviest. If either of those two are heavier, then that's the heaviest orange.

Note:
There are already several puzzles about very similar weighing problems on Puzzling SE, so don't be too surprised if this question doesn't get a ton of positive feedback or is flagged as a duplicate. Don't take it personally, but in the future remember to look at similar questions to make sure it hasn't been asked before.

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    $\begingroup$ You beat me to it. $\endgroup$ – padawan Jan 12 '18 at 21:12
  • $\begingroup$ That was fast lol, I did searched before posting this one and didn't find something similar. I don't get it personal if it is down voted or marked as duplicate. $\endgroup$ – achref Jan 12 '18 at 21:13
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    $\begingroup$ @achref Usually these questions use coins instead of oranges, so a search for "Coin Weighing" problems would show a lot of similar ones. There's also a tag, "weighing", specifically for this sort of problem. I don't know if this exact one has been done before, but certainly several similar ones. Either way, welcome to Puzzling, and good luck with creating & solving puzzles in the future :) $\endgroup$ – DqwertyC Jan 12 '18 at 22:06
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Weigh 3 against 3, if equal then one of the other 3 is heaviest. If one side was heavy then weigh one against one, if balanced then the third one is heaviest if not the heaviest is on the scale.

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