Insight · ★★★☆☆ · ~7 min
Four Weights
Weigh any load 1–40 g on a balance. How few weights do you need?
by MindYourPuzzle
A merchant's puzzle from 1600s recreational math — the trick is using a number base you've probably never used.
You have a balance scale and want to weigh out any whole number of grams from 1 to 40. You may place weights on either pan (including the same side as the object being weighed).
What is the minimum number of weights you need — and what are their values?
(Answer with the number of weights.)
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