Multiple choice general knowledge math & puzzles

A, B and C start at the same time in the same direction to run around a circular stadium. A completes a round in 252 seconds, B in 308 seconds and c in 198 seconds, all starting at the same point. After what time will they again at the starting point ?

  1. 26 minutes and 18 seconds

  2. 42 minutes and 36 seconds

  3. 45 minutes

  4. 46 minutes and 12 seconds
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

LCM of 252, 308, 198 seconds = 2772 seconds = 46 minutes 12 seconds. Prime factors: 252=2²×3²×7, 308=2²×7×11, 198=2×3²×11. LCM=2²×3²×7×11=2772.

AI explanation

To find when A, B, and C next meet at the starting point together, we need the LCM of their lap times: 252, 308, and 198 seconds. Factoring gives LCM = 2² × 3² × 7 × 11 = 2772 seconds, which converts to 46 minutes and 12 seconds.

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