Doesn't work that way Brian as you are trying to add 25% of the lesser figure to get back to the original....which can't work.
An easy example is 400 dyno hp...that will loose 25% at the wheels -

400 - 25% (or times .75 if you like) = 300hp

To work from the other way round...

300 + 25% ( x 1.25) = 375hp ..... just lost 25hp

The second calculation is obviously wrong as you are using 25% of the CORRECTED figure to try to get back to the original....can't work.