May I receive help on this question? Its going to be due soon

Does anyone know how to do geometryme with this problem

Alcoa was $10.02 a share yesterday. today it is at $9.75 a share. if you own 50 shares, did ou have capital gain or loss ? how much of a gain or loss did you have ? express the capital gain/loss as a percent of the original price

Collin did the work to see if 10 is a solution to the equation r/4=2.4