Question

A bell rings every 15 seconds another bell rings every 30 seconds. At 3:00 pm the two bells ring simultaneously. At what time will the bells ring again at the same time

Answer 1

$\huge\sf\pink{Answer}$

☞ They will ring simultaneously at 3:00:30 pm

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$\huge\sf\blue{Given}$

✭ A bell rings every 15 seconds

✭ Another bell rings every 30 seconds

✭ They ring together at 3:00 pm

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$\huge\sf\gray{To \:Find}$

☆ Time when they will ring simultaneously again?

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$\huge\sf\purple{Steps}$

So here your answer can simply be found by finding the LCM of 15 and 30

➝ 15 = 3 × 5

➝ 30 = 2 × 5 ×3

So now their LCM = $\sf\orange{2 × 5 × 3}$

LCM(15,30) = 30

So they both will ring back again after 30 seconds that is they will ring back at, 3:00:30

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