Question

show that 1 and only 1 out of n,n+4,n+8,n+12 and n+16 is divisible by 5, where n is any positive integer​

Answer 1

put 5 in n,n+4,n+8,,n+12 and n+16

the answer u get is

5,9,13,17 and 21 only 5 is divisible by 5