A book rental shop rented out books and the rate of rental charges are shown in the table.
Number of days |
Rates |
After the first 9 days |
50 cents a day |
After 9 days |
70 cents a day |
John rented 3 books and was charged $30.30. How many days did he rent the books for?
$1 = 100¢
$30.30 = 30.30 x 100 = 3030¢
Amount that John paid for each book
= 3030 ÷ 3
= 1010¢
Amount that John paid for each book for renting for the first 9 days
= 9 x 50
= 450¢
Additional amount that John paid for each book for renting for additional days
= 1010 - 450
= 560¢
Number of additional days that John rented for each book
= 560 ÷ 70
= 8
Total number of days that John rented the books
= 9 + 8
= 17
Answer(s): 17