coin was to weigh exactly ten grams of pure gold.

One of the goldsmiths was a bad man. He decided to cheat. He

made all his ten coins one gram short. Now the Sultan heard that

one of the goldsmiths had cheated. He also heard that this man

had made each of his coins 1 gram short.

So what's the minimum number of weighing needed for the

clever Sultan to find out the culprit?

Note: Not balance scale but a weight scale i.e. tells you number of grams.

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(2)

ok, since you dudes so bright, here's a tougher one I just remembered:

If you given 2 NON-UNIFORM candles, all we know is each can be burnt in 1 hour's time.

How can you use them to time 45min?

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(3) Thanks to ... illusion88

You are asked to find the height of a very tall building. The only equipment you are given is a very expensive, very percise barometer and a watch. Tell me three ways to find the height of the building using the barometer the watch.