You build and sell toy cars for $36 each. so far, you have built 25 toy cars. how many more toy cars will you have to build and sell to earn $1,620?

If you have built 25 cars, and they are 36 dollars per, then multiply 25 and 36 for the amount of money.  This will result with 25*36=900.  Since we already have 900 dollars worth, we subtract that from the goal of 1620, leaving us with 1620-900=720.  Now, divide this by the price per car for the amount of cars needed to get to this goal. 720/36=20 cars

Hope this helps!

He needs to build 20 more cars-
25 x $36 = 900
(1620-900)/36=20