Question

Lemon was going through some flashcards and found the following factor sets. 47 x 69 31 x 59 45 x 70 21 x 19 Which of the factor pairs contains only prime numbers? 47 x 69 31 x 59 21 x 19 45 x 70

Answer 1

Notice that 45 and 70 are divisible by 5, thus, they are not prime

Next, 21 nd 69 are divisible by 3, then its not prime.

The only prime numbers in the factors are 47,31,59 and 19

Therefore, the only factor pair that contains only prime numbers is 31 x 19