Avendor pays a rock band 13 of the total profit from t-shirts and sweatshirts sold at every concert. the vendor paid the rock band $726 after the last concert. if the profit from t-shirts sales was $1,632, what was the profit from sweatshirt sales?

Let's call
 x = profit from the sweatshirt sales
 1) A vendor pays to rock band 13% of the total profit from T-shirts and sweatshirts sold at every concert.
 2) the profit from T-shirts sales was $ 1,632
 3) The vendor paid the rock band $ 726 after the last concert
 We then have the following equation:
 0.13 * (1632 + x) = 726
 Clearing x:
 (1632 + x) = (726 / 0.13)
 x = (726 / 0.13) - 1632 = 3953 $
 
 the profit from sweatshirt sales was 3953 $