Higher June 2022 Paper 3 Q4

4 Jo is going to buy 15 rolls of wallpaper.

Here is some information about the cost of rolls of wallpaper from each of two shops.

Chic Decor	Style Papers
3 rolls for £36	Pack of 5 rolls normal price £70 12% off the normal price

Jo wants to buy the 15 rolls of wallpaper as cheaply as possible.

Should Jo buy the wallpaper from Chic Decor or from Style Papers?
You must show how you get your answer. (4)

Mark scheme

Answer	Mark	Mark scheme
Chic Decor with correct supporting evidence	P1	for process to find cost of 15 rolls from Chic Decor, eg \(\dfrac{15}{3} \times 36\ (= 180)\) or for process to find cost of 15 rolls from Style Papers at normal price, eg \(\dfrac{15}{5} \times 70\ (= 210)\) or for process to find cost of 1 roll from Chic Decor, eg \(36 \div 3\ (= 12)\) or for process to find cost of 1 roll from Style Papers, eg \(70 \div 5\ (= 14)\) or for process to find the cost of 5 rolls from Chic Decor, eg \(\dfrac{36}{3} \times 5\ (= 60)\)
	P1	for any first step in using the discount at Style Papers, eg \(0.12 \times \text{``}210\text{''}\ (= 25.2(0))\) or \(0.12 \times \text{``}14\text{''}\ (= 1.68)\) or \(0.12 \times 70\ (= 8.4(0))\) or \(1 - 0.12\ (= 0.88)\)
	P1	for full process to find cost from Style Papers, eg \(\text{``}210\text{''} - \text{``}25.2\text{''}\) oe \((= 184.8(0))\) or \(\text{``}0.88\text{''} \times \text{``}210\text{''}\) or for \(\text{``}14\text{''} - \text{``}1.68\text{''}\) oe \((= 12.32)\) or \(\text{``}0.88\text{''} \times \text{``}14\text{''}\) or for \(70 - \text{``}8.4(0)\text{''}\) oe \((= 61.6(0))\) or \(\text{``}0.88\text{''} \times 70\)
	C1	for Chic Decor with fully correct figures eg 180 and 184.8(0) or 12 and 12.32 or 60 and 61.6(0)

Could compare the costs for any number of rolls