ArithmeticQuestion 337 of 550

One bell rings every 4 minutes, a second every 6 minutes and a third every 10 minutes. They ring together now. After how many minutes do they ring together again?

  1. 30 minutes
  2. 120 minutes
  3. 60 minutes
  4. 40 minutes
Show answer

Correct answer: 60 minutes

Find the lowest common multiple of 4, 6 and 10. 4 = 2², 6 = 2 × 3 and 10 = 2 × 5. So it is 2² × 3 × 5 = 60.

Test structure: ETEC guide to the GAT

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Questions last reviewed: 21 October 2026