Question

Two bells ring at an interval of 30 minutes and 36 minutes.They ring simultaneously at 8:30 a.m.When will they ring simultaneously again?

Answer 1

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☞ Both the bells will ring simultaneously again at 11:30

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$\huge\sf\blue{Given}$

✭ Two bells ring at an interval of 30 & 36 minutes

✭ They rang simultaneously at 8:30 am

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◈ When will they ring back together again?

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So here we shall first find the HCF of 30 & 36, that is,

➝ 30 = 2 × 3 × 5

➝ 36 = 2 × 2 × 3 × 3 = 2² × 3²

LCM is the product of the least power of the common factors,so,

➝ LCM(30,36) = 2² × 3² × 5

➝ LCM(30,36) = 180

So it means that the two bells will ring again in 180 minutes,so if we had to show it from 8:30 we have to convet 180 minutes to hours, that is,

➳ $\sf 1 \ Hour = 60 \ Minutes$

➳ $\sf 180 \ Minutes = \dfrac{180}{60}$

➳ $\sf \red{180 \ Minutes = 3 \ Hours}$

Adding it to 8:30 am

»» $\sf 8:30 + 3$

»» $\sf \orange{11:30 \ Am}$

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