The advertisement shows the cost of buying pens from a stationery kiosk.
- Penelope bought 18 pens. How much did she pay?
- Tom bought 90 pens. How much did he pay?
(a)
Number of sets of 15 pens
= 18 ÷ 15
= 1 r 3
Cost of first 15 pens
= 15 x 1.70
= $25.50
Cost of the next 3 pens
= 3 x 1.30
= $3.90
Amount that Penelope paid
= 25.50 + 3.90
= $29.40
(b)
Number of pens that was not part of the first 15 pens
= 90 - 15
= 75
Cost of first 15 pens = $25.50
Cost of the next 75 pens
= 75 x 1.30
= $97.50
Total cost of 90 pens before an additional discount of 6% is applied
= 25.50 + 97.50
= $123
Amount that Tom paid in percent after an additional discount of 6% is applied
= 100% - 6%
= 94%
100% of the total cost of 90 pens = 123
1% of the total cost of 90 pens = 123 ÷ 100 = 1.23
94% of the total cost of 90 pens = 94 x 1.23 = 115.62
Amount that Tom paid = $115.62
Answer(s): (a) $29.40; (b) $115.62