- #1
Robb
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Homework Statement
Consider a set of boxes, each containing 20 balls. Suppose every ball weighs one pound, except that the balls in one box are all one ounce too heavy or one ounce too light. A precise scale is available that can weigh to the nearest ounce (not a balance scale). By selecting some balls to place on the scale, explain how to determine in one weighing which is the defective box and whether its balls are too heavy or too light.
Homework Equations
The Attempt at a Solution
Take one ball from the first box, two from the second box, three from the third etc.
Hence, Σn, from n=1 to 20. I'm not sure how to determine which is the defective box and whether it's too heavy or too light. Please advise.