The advertisement shows the cost of buying pencils from a stationery shop.
- Abi bought 22 pencils. How much did she pay?
- Simon bought 70 pencils. How much did he pay?
(a)
Number of sets of 15 pencils
= 22 ÷ 15
= 1 r 7
Cost of first 15 pencils
= 15 x 2.30
= $34.50
Cost of the next 7 pencils
= 7 x 1.90
= $13.30
Amount that Abi paid
= 34.50 + 13.30
= $47.80
(b)
Number of pencils that was not part of the first 15 pencils
= 70 - 15
= 55
Cost of first 15 pencils = $34.50
Cost of the next 55 pencils
= 55 x 1.90
= $104.50
Total cost of 70 pencils before an additional discount of 10% is applied
= 34.50 + 104.50
= $139
Amount that Simon paid in percent after an additional discount of 10% is applied
= 100% - 10%
= 90%
100% of the total cost of 70 pencils = 139
1% of the total cost of 70 pencils = 139 ÷ 100 = 1.39
90% of the total cost of 70 pencils = 90 x 1.39 = 125.10
Amount that Simon paid = $125.10
Answer(s): (a) $47.80; (b) $125.10