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 7 days |
60 cents a day |
After 7 days |
90 cents a day |
Julian rented 4 books and was charged $31.20. How many days did he rent the books for?
$1 = 100¢
$31.20 = 31.20 x 100 = 3120¢
Amount that Julian paid for each book
= 3120 ÷ 4
= 780¢
Amount that Julian paid for each book for renting for the first 7 days
= 7 x 60
= 420¢
Additional amount that Julian paid for each book for renting for additional days
= 780 - 420
= 360¢
Number of additional days that Julian rented for each book
= 360 ÷ 90
= 4
Total number of days that Julian rented the books
= 7 + 4
= 11
Answer(s): 11