Which of the following numbers are prime? (a) 23 (b) 51 (c) 37 (d) 26
(a) 23 23 has only two factors, 1 and 23 therefore, it is a prime number. (b) 51 51 has 1, 3, 17 , 51 , not a prime number (c) 37 37 has 1 and 37 , it is a prime number (d) 26 26 has 1, 2, 13 , 26, not a prime number.
