Question

The prime factorization of a number is 32 x 58 x 7. Which statement is true about the factors of the number?

OTwenty-one is a factor of the number because both 3 and 7 are prime factors.
OTwenty-one is not a factor of the number because 21 is not prime.
O Ninety is a factor of the number because 32 = 9 and 90 is divisible by 9.
O Ninety is not a factor of the number because 90 is not divisible by 7.
No

Answer 1

Twenty-one is a factor of the number because both 3 and 7 are prime factors.

Explanation:

32 and 58 are not prime numbers, so we assume your factorization is supposed to be ...

3^2 × 5^8 × 7

Both 3 and 7 are factors, so 3·7 = 21 will be a factor of the number. (Matches the first choice.)

Ninety is not a factor, because 90 is 2×3^2×5 and 2 is not among the factors given.