There's a quick, easy, sloppy way, and there's a good math way.
Here's the good math way:
If the integers are consecutive, then you can call them 'x', (x+1), and (x+2).
We know what their sum is, so let's add them up:
x + (x+1) + (x+2) = 336
x + x+1 + x+2 = 336
Combine the terms that are alike on the left side:
3x + 3 = 336
Subtract 3 from each side: 3x = 333
Divide each side by 3 : x = 111
The integers are 111, 112, and 113 .