2 cannot take away 3 so you borrow from the 7 and 7 becomes 6 you add the 1 you took from 7 place with 2 and becomes twelve, twelve take away 3 is 9, 6 cannot take away from 7 so you borrow from 4 and 4 becomes 3 and you add 1 to the 6 and becomes 16, 16 take away 7 is 9, 3-1 is 2.
You have to add the 480 dollars which eliminates A and C. Then, when finding commission you make the commission rate into decimal form which eliminates D. Your only option left is B
