You are given 8 balls, and one will be slightly heavier or lighter than the others. How can you find the heavier or lighter ball in only 2 weighings on a balance scale?
Q1. You are given 8 balls, and one will be slightly heavier or lighter than the others. How can you find the heavier or lighter ball in only 2 weighings on a balance scale?
Answer: Weigh 3 against 3, then if unbalanced, weigh 1 of the 3 against another. If balanced, weigh the remaining 2 against each other
Explanation: First weighing: 3 vs 3. If unbalanced, take the heavier/lighter 3 and weigh 1 vs 1. If still unbalanced, the heavier/lighter one is identified. If balanced, the remaining is the heavier/lighter one.