This math skill teaches how to determine if one number is a multiple of another using prime factorization. It involves identifying all the prime factors of both numbers and checking if the prime factors of one number are contained within the factors of the other.
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Determining whether one number is a multiple of another
Test your understanding of is number a multiple of another by practicing it! Work through the below exercises to use it in practice.
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Is 120 a multiple of 15. Let's use prime factorization to find out.
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First let's find the prime factors of each number. For example, 15 is 5 times 3.
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If we express them in exponent form it will be a bit easier to see what is happening. So, for 120, 2 times 2 times 2 can be written as 2 to the power of 3
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For a number to be a multiple of another number it must have every one of the prime factors of the other number. For 15, we have a 5, and a 3.
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120 has both a 5 and a 3 in its prime factors, so 120 is a multiple of 15