The advertisement shows the cost of buying files from a bookstore.
- Sabrina bought 18 files. How much did she pay?
- George bought 80 files. How much did he pay?
(a)
Number of sets of 15 files
= 18 ÷ 15
= 1 r 3
Cost of first 15 files
= 15 x 2.30
= $34.50
Cost of the next 3 files
= 3 x 2.10
= $6.30
Amount that Sabrina paid
= 34.50 + 6.30
= $40.80
(b)
Number of files that was not part of the first 15 files
= 80 - 15
= 65
Cost of first 15 files = $34.50
Cost of the next 65 files
= 65 x 2.10
= $136.50
Total cost of 80 files before an additional discount of 8% is applied
= 34.50 + 136.50
= $171
Amount that George paid in percent after an additional discount of 8% is applied
= 100% - 8%
= 92%
100% of the total cost of 80 files = 171
1% of the total cost of 80 files = 171 ÷ 100 = 1.71
92% of the total cost of 80 files = 92 x 1.71 = 157.32
Amount that George paid = $157.32
Answer(s): (a) $40.80; (b) $157.32