Question
An electronic device makes a beep after every 60 seconds. Another device makes a beep after 62 seconds. They beeped together at 10 a.m. At what time will they beep together at the earliest?
✓
Answer
Interval of beeping together = LCM (60 seconds, 62 seconds)
The prime factorization of 60 and 62:
60 = 30 × 2, 62 = 31 × 2
$\therefore$ L.C.M of 60 and 62 is 30 31 × 2 = 1860 sec = 31min
$\therefore$ electronic device will beep after every 31 minutes
After 10 a.m., it will beep at 10hrs 31 minutes
The prime factorization of 60 and 62:
60 = 30 × 2, 62 = 31 × 2
$\therefore$ L.C.M of 60 and 62 is 30 31 × 2 = 1860 sec = 31min
$\therefore$ electronic device will beep after every 31 minutes
After 10 a.m., it will beep at 10hrs 31 minutes
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