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Problem #2 EASY

Burning Ropes of Time

Microsoft Math Lateral Thinking

Problem Statement

You are given two ropes of uneven density and a box of matches. Each rope takes exactly 60 minutes (1 hour) to burn completely from one end to the other. Because the ropes have uneven density, they do not burn at a constant rate. For example, half of a rope might burn in 10 minutes while the remaining half takes 50 minutes. You cannot cut the ropes or measure them by length. How can you use these ropes to measure exactly 45 minutes?

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