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The lcm of 120 and n is 2520. Find the smallest value of n.

Please explain the answer. Thank you.

User Ruds
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1 Answer

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Answer: The smallest value of n is:

n = 21

Explanation:

We know that the LCM (least common multiple) between 120 and n is 2520.

We want to find the smallest value of n.

The smallest value of n will be such that n does not share any prime number with 120, then the greatest common factor between 120 and n is 1.

Remember that the LCM between A and B is:

LCM(A, B) = A*B/(GCM(A, B))

Then if the greatest common factor between A and B is 1, we will have:

LCM(A, B) = A*B

Then if the greatest common factor between 120 and n is 1, we have that:

LCM(120, n) = 120*n = 2520

then:

n = 2520/120 = 21

The smallest value of n is n = 21.

User Rokia
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