Question

A list is made of all possible 2-digit whole numbers that result from using only the digits 1,3,5, and 7 in both the

ones and tens place, with duplications allowed. How many whole numbers in the list are prime numbers?

A.6
B.7
C.8
D.9
E.10​

Answer 1

I think 8.
11, 13, 17, 31, 37, 53, 71, 73
Good luck