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Counting Sand (Posted on 2005-04-07) Difficulty: 2 of 5
Count Sandini calls himself the greatest "Sand Counter" in the world. Show him a bucket filled of sand, and in a few seconds he will tell you how many grains of sand are there!

Can you devise a (fairly quick) test to prove whether he can actually do so, or if he's a fraud?

See The Solution Submitted by Federico Kereki    
Rating: 3.3333 (3 votes)

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Some sand counting ability? | Comment 8 of 9 |
(In reply to A variation by Old Original Oskar!)

Similar to other variations, if you have two buckets, have him state how many grains are in each bucket, and then remove sand from one (messing up the sand in both) and then ask him which one you removed sand from. Repeat this until you are convinced.

However as with the suggestions here, passing the test does not confirm the stated powers -- it simply shows he has some sand-counting powers. Passing this test means he can tell which bucket has a different amount of sand, which is weaker than counting sand quickly.

Similarly, in the commonly stated solution of taking out a few grains, passing this test would show he can give net change in amount of sand. This is stronger than the above test (though it would take longer to do), but still weaker than counting sand quickly.

So if he passes, you won't be sure if he has the ability he stated or some weaker version.

  Posted by Gamer on 2011-08-09 02:59:05

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