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 4 days |
40 cents a day |
After 4 days |
70 cents a day |
Sean rented 3 books and was charged $21.60. How many days did he rent the books for?
$1 = 100¢
$21.60 = 21.60 x 100 = 2160¢
Amount that Sean paid for each book
= 2160 ÷ 3
= 720¢
Amount that Sean paid for each book for renting for the first 4 days
= 4 x 40
= 160¢
Additional amount that Sean paid for each book for renting for additional days
= 720 - 160
= 560¢
Number of additional days that Sean rented for each book
= 560 ÷ 70
= 8
Total number of days that Sean rented the books
= 4 + 8
= 12
Answer(s): 12