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 |
20 cents a day |
After 7 days |
30 cents a day |
Zeph rented 3 books and was charged $8.70. How many days did he rent the books for?
$1 = 100¢
$8.70 = 8.70 x 100 = 870¢
Amount that Zeph paid for each book
= 870 ÷ 3
= 290¢
Amount that Zeph paid for each book for renting for the first 7 days
= 7 x 20
= 140¢
Additional amount that Zeph paid for each book for renting for additional days
= 290 - 140
= 150¢
Number of additional days that Zeph rented for each book
= 150 ÷ 30
= 5
Total number of days that Zeph rented the books
= 7 + 5
= 12
Answer(s): 12