Question
Three bells ring at intervals of 18 seconds, 24 seconds
and 32 seconds. If they all ring together at 8:00:00 a.m., at what time will they next ring together?Solution
We need the LCM of 18, 24 and 32. Prime factors: 18 = 2 × 3² 24 = 2³ × 3 32 = 2⁵ LCM = 2⁵ × 3² = 32 × 9 = 288 seconds 288 s = 4 minutes 48 seconds So, next time together = 8:00:00 + 4 min 48 s = 8:04:48 a.m.
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