The advertisement shows the cost of buying pencils from a stationery shop.
- Usha bought 21 pencils. How much did she pay?
- Wesley bought 50 pencils. How much did he pay?
(a)
Number of sets of 15 pencils
= 21 ÷ 15
= 1 r 6
Cost of first 15 pencils
= 15 x 3.90
= $58.50
Cost of the next 6 pencils
= 6 x 3.70
= $22.20
Amount that Usha paid
= 58.50 + 22.20
= $80.70
(b)
Number of pencils that was not part of the first 15 pencils
= 50 - 15
= 35
Cost of first 15 pencils = $58.50
Cost of the next 35 pencils
= 35 x 3.70
= $129.50
Total cost of 50 pencils before an additional discount of 3% is applied
= 58.50 + 129.50
= $188
Amount that Wesley paid in percent after an additional discount of 3% is applied
= 100% - 3%
= 97%
100% of the total cost of 50 pencils = 188
1% of the total cost of 50 pencils = 188 ÷ 100 = 1.88
97% of the total cost of 50 pencils = 97 x 1.88 = 182.36
Amount that Wesley paid = $182.36
Answer(s): (a) $80.70; (b) $182.36
