# MO C–I–1 2018

An unknown number is divisible by just four numbers from the set {6, 15, 20, 21, 70}. Determine which ones.

Result

x = (Correct answer is: 6,15,21,70)

#### Solution:

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#### To solve this example are needed these knowledge from mathematics:

Do you want to calculate least common multiple two or more numbers? Do you want to calculate greatest common divisor two or more numbers?

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