Weighing 1 to 121 Puzzle - Solution

The Puzzle:

Using a balance-type scale with weighing pans, you need to be able to measure all weights from 1g to 121g (to the nearest 1g).

How many weights would you need? You can place the weights on either or both pans.

Our Solution:

You need 5 weights: 1g, 3g, 9g, 27g, 81g.

Example: to weigh 50g, have 81g on one side, and 27g, 3g and 1g (and your object) on the other.

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