Question

a,b,c are prime numbers
a.b - b.c =23
a+b+c=?

a) 30
b) 28
c) 26
d) 24
e)22

Answer 1

26 is the right answers of this question

Answer 2

(a)23 has only two factors, 1 and 23 therefore, it is a prime number.

(b) 51 has 1, 3, 17 , 51 , not a prime number

(c) 37 has 1 and 37 , it is a prime number

(d) 26 has 1, 2, 13 , 26, not a prime number.