The advertisement shows the cost of buying notebooks from a shop.
- Cindy bought 17 notebooks. How much did she pay?
- Sean bought 70 notebooks. How much did he pay?
(a)
Number of sets of 15 notebooks
= 17 ÷ 15
= 1 r 2
Cost of first 15 notebooks
= 15 x 2.90
= $43.50
Cost of the next 2 notebooks
= 2 x 2.70
= $5.40
Amount that Cindy paid
= 43.50 + 5.40
= $48.90
(b)
Number of notebooks that was not part of the first 15 notebooks
= 70 - 15
= 55
Cost of first 15 notebooks = $43.50
Cost of the next 55 notebooks
= 55 x 2.70
= $148.50
Total cost of 70 notebooks before an additional discount of 9% is applied
= 43.50 + 148.50
= $192
Amount that Sean paid in percent after an additional discount of 9% is applied
= 100% - 9%
= 91%
100% of the total cost of 70 notebooks = 192
1% of the total cost of 70 notebooks = 192 ÷ 100 = 1.92
91% of the total cost of 70 notebooks = 91 x 1.92 = 174.72
Amount that Sean paid = $174.72
Answer(s): (a) $48.90; (b) $174.72