The advertisement shows the cost of buying files from a bookstore.
- Kimberly bought 22 files. How much did she pay?
- Tom bought 50 files. How much did he pay?
(a)
Number of sets of 15 files
= 22 ÷ 15
= 1 r 7
Cost of first 15 files
= 15 x 2.50
= $37.50
Cost of the next 7 files
= 7 x 2.10
= $14.70
Amount that Kimberly paid
= 37.50 + 14.70
= $52.20
(b)
Number of files that was not part of the first 15 files
= 50 - 15
= 35
Cost of first 15 files = $37.50
Cost of the next 35 files
= 35 x 2.10
= $73.50
Total cost of 50 files before an additional discount of 3% is applied
= 37.50 + 73.50
= $111
Amount that Tom paid in percent after an additional discount of 3% is applied
= 100% - 3%
= 97%
100% of the total cost of 50 files = 111
1% of the total cost of 50 files = 111 ÷ 100 = 1.11
97% of the total cost of 50 files = 97 x 1.11 = 107.67
Amount that Tom paid = $107.67
Answer(s): (a) $52.20; (b) $107.67
