The expression for the sum of the three integers is 3n.
If <em>n</em> is the middle number of three consecutive numbers, then the number before <em>n</em> is (<em>n - 1)</em> and the number after <em>n </em> is (<em>n +1). </em>By adding the three terms, we get an expression for its sum:. Simplifying the expression yields 3n. I hope this helps.