Question 16476
Try this:

Let the first number be x, then the next consecutive number will be x+1 and the third consecutive number will be x+2 and they should all add up to 600.

{{{x + (x+1) + (x+2) = 600}}} Simplify.
{{{3x + 3 = 600}}} Subtract 3 from both sides.
{{{3x = 597}}} Divide both sides by 3.
{{{x = 199}}}

The three consecutive numbers are: 199, 200, and 201.