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 |
40 cents a day |
Seth rented 2 books and was charged $6.80. How many days did he rent the books for?
$1 = 100¢
$6.80 = 6.80 x 100 = 680¢
Amount that Seth paid for each book
= 680 ÷ 2
= 340¢
Amount that Seth paid for each book for renting for the first 7 days
= 7 x 20
= 140¢
Additional amount that Seth paid for each book for renting for additional days
= 340 - 140
= 200¢
Number of additional days that Seth rented for each book
= 200 ÷ 40
= 5
Total number of days that Seth rented the books
= 7 + 5
= 12
Answer(s): 12