Joann bought 8 books and a textbook.

Question

Joann bought 8 books and a textbook. She paid $200 to the cashier and received $20 change. If the textbook cost 7 times as much as each book, find the cost of the textbook.

 

Please tell me the final answer.

Answer 1

Let b = cost of a book
Let T = cost of a textbook

 

She spent $200 and got $20 back

for 8 books and a textbook:

 

8b + T = 200 - 20

1)  8b + T = 180

 

2)  T = 7b

 

Substitute 7b in place of T in equation 1 and solve for b.

Then multiply that amount by 7 to get the cost of a textbook