Three consecutive numbers that have a sum of 159. What are the numbers?

The middle one is their average, 159/3 = 53.

The numbers are 52, 53, 54.

Let n = the first number. n + 1 = the second and n + 2 = the third number. So ...

n + (n + 1) + (n + 2) = 159

3n + 3 = 159

3n = 156

n = 52

n + 1 = 53

n + 2 = 54

So the numbers are 52, 53, and 54.