Clearly you are trying to do
something; those numbers (1500, 1.1%, ...) come from
somewhere! So you have not stated the
problem you are "solving". We would expect to see something like, "If I earn a total of $31,500 over y years, and ... , how much ...?"
As has been said, the
work is nominally correct (as long as you are taking 2,625/my as 2,625/(my), which is not universally accepted); so if the numbers you use are correct for whatever you are trying to do, your answers are correct. Unfortunately, I can't think of a problem for which your work would be appropriate.
In particular, if as you just said, you are earning $31,500
per year, then your work is entirely wrong. What you originally wrote takes the letters as variables, but now you are using them as units. There is a big difference between units and variables! (See
here.) I don't even know what a "month-year" would mean! Instead, you would divide by "12 months
per year" to get the amount you earn
per month; then maybe multiply by 1.1% to find the amount per month at that tax rate or something; and so on.
Do you see yet why we need to see what you are trying to accomplish, whether it is a textbook exercise or a personal calculation?