Question

Question 11

Write five pairs of prime numbers less than 20 whose sum is divisible by 5.
[Hint: 3 + 7 = 10]

Answer 1

Prime Numbers less than 20 are 2, 3, 5, 7, 11, 13, 17, 19

2 + 3 = 5; 5 is divisible by 5
7 + 13 = 20; 20 is divisible by 5
3 + 17 = 20; 20 is divisible by 5
2 + 13 = 15; 15 is divisible by 5
13 + 17 = 30; 30 is divisible by 5