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 |
30 cents a day |
After 9 days |
60 cents a day |
Oscar rented 4 books and was charged $25.20. How many days did he rent the books for?
$1 = 100¢
$25.20 = 25.20 x 100 = 2520¢
Amount that Oscar paid for each book
= 2520 ÷ 4
= 630¢
Amount that Oscar paid for each book for renting for the first 9 days
= 9 x 30
= 270¢
Additional amount that Oscar paid for each book for renting for additional days
= 630 - 270
= 360¢
Number of additional days that Oscar rented for each book
= 360 ÷ 60
= 6
Total number of days that Oscar rented the books
= 9 + 6
= 15
Answer(s): 15