Question 536313
If he has weights of 1, 2, 4 & 8 kilos, he can make all integer values up to 15 kilos.
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If he has weights of 1, 3, 9 & 27 kilos, he can make all up to 40 kilos, but he has to have 2 of each of the 1, 3 & 9 kilo weights.
He needs 1, 1, 3, 3, 9, 9 & 27 kilo weights
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I think something isn't right in the problem.
With only 1 of each he can make
1, 3, 4, 9, 10, 12, 13, 27, 28, 30, 36, 37, 39 & 40 kilos.
2, eg, is not possible.