You can
put this solution on YOUR website!Your task here is mainly to write an equation. Write it in words first:
number PLUS same number PLUS same 1.25 * number = 2400.
Replace number with x:
x + x + 1.25*x = 2400
3.25*x = 2400
this equation does not solve for a natural number x, the result is x = 738.461..., which makes me suspect that you either mis-stated the problem or I did not understand it.