There were 10 students who were semi-finalists in the science fair. The judges selected 7 students to move on to the finals. Find the percent of decrease.

So don't take my word i'm not exactly a mathematical person but i would assume a. because while selling the soap every month you increase in sells so you would by 11 percent. the you would get the factor 0.89 which if i had to guess would be the monthly profit over 11 probably wrong tho