Question

show that one and only one out of n , n+1and n+2 is divisible by 3 where n is any positive integer

Answer 1

For any number x, if a is a multiple of it, then the next multiples are a+x, a+2x and so on.

For this case, x is specified as 3 and of n is a multiple of it, then the next multiple cannot be smaller than n+3, so n+1 and n+2 cannot be multiples.

Similarly, the others may be assumed as multiples and the method will remain the same.

Hope I helped.

Answer 2

This a 12th based answer... As it's the best and suitable way to solve it.... Hope it helps...