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 |
40 cents a day |
After 7 days |
90 cents a day |
Ken rented 2 books and was charged $18.20. How many days did he rent the books for?
$1 = 100¢
$18.20 = 18.20 x 100 = 1820¢
Amount that Ken paid for each book
= 1820 ÷ 2
= 910¢
Amount that Ken paid for each book for renting for the first 7 days
= 7 x 40
= 280¢
Additional amount that Ken paid for each book for renting for additional days
= 910 - 280
= 630¢
Number of additional days that Ken rented for each book
= 630 ÷ 90
= 7
Total number of days that Ken rented the books
= 7 + 7
= 14
Answer(s): 14