Question
An electronic device makes a beep after every 60 sec.
Another device makes a beep after every 62 sec. They beeped together at 10 a.m. The next time, when they would beep together at the earliest is:Solution
LCM of (60,62)=2² × 3 × 5 × 31 = 4 × 3 × 5 × 31 = 60 × 31 = 1860 seconds. Convert 1860 seconds to minutes and seconds 1860 ÷ 60 = 31 minutes They will beep together again after 31 minutes, so the next time is: 10:31 a.m.
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