The advertisement shows the cost of buying notebooks from a stationery shop.
- Erika bought 27 notebooks. How much did she pay?
- John bought 90 notebooks. How much did he pay?
(a)
Number of sets of 15 notebooks
= 27 ÷ 15
= 1 r 12
Cost of first 15 notebooks
= 15 x 3.10
= $46.50
Cost of the next 12 notebooks
= 12 x 2.90
= $34.80
Amount that Erika paid
= 46.50 + 34.80
= $81.30
(b)
Number of notebooks that was not part of the first 15 notebooks
= 90 - 15
= 75
Cost of first 15 notebooks = $46.50
Cost of the next 75 notebooks
= 75 x 2.90
= $217.50
Total cost of 90 notebooks before an additional discount of 8% is applied
= 46.50 + 217.50
= $264
Amount that John paid in percent after an additional discount of 8% is applied
= 100% - 8%
= 92%
100% of the total cost of 90 notebooks = 264
1% of the total cost of 90 notebooks = 264 ÷ 100 = 2.64
92% of the total cost of 90 notebooks = 92 x 2.64 = 242.88
Amount that John paid = $242.88
Answer(s): (a) $81.30; (b) $242.88
