What is the equation for finding a number that is X% less than another number? I know this seems like a juvenile question, but for some reason I can't recall how to do this.
Lets say I want to find 87 reduced by 99.75%. What is the equation to do that?
Thanks!

If you want $X$% of 87, multiply the latter by $\frac{X}{100}$. (So, for example, to get 25 percent, you multiply by $0.25$).
If by "reduced by 99.75%" you mean 99.75% of the total, then, multiply by $.9975$. If "reduced by 99.75%" means taking 99.75% off (so you are left with only 0.25%), then multiply by $0.0025$. 
