Question

What is the algebraic expression for the sum of three consecutive integer?

Answer 1

Sum of three consecutive integer number is 3 times the middle value: That is 3n given that the mean number is n.

Explanation:

Let any integer number be n
Then the number 1 less than it is n-1
Also the number 1 more than it is n+1

So the sum is `(n-1) + n + n(+1)`
Adding these we have `n+n+n+1-1`
So the final sum is `3n`

Note: the mean value is `3n/3 = n`