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Three bells toll every 15 minutes, 30 minutes, and 45 minutes. If they toll together at 8 : 30 a.m. What is the next time they toll together?

Three bells toll every 15 minutes, 30 minutes, and 45 minutes. If they toll together at 8 : 30 a.m. What is the next time they toll together? Correct Answer 10 : 00 am

Concept:

LCM of (2, 4) is 4. 

Calculation:

⇒ The three bells toll together after LCM of (15, 30, 45) = 90 minutes = 1.5 hours

⇒ After 8 : 30 a.m., they toll together again at 10 : 00 a.m.

∴ The required result will be 10 : 00 a.m.

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