Final answer:
After calculating the total cost at each store, Carly should buy her paint from The DIY shop, the total cost being £22.50, making it the cheapest option.
Step-by-step explanation:
To determine which store Carly should buy her 10 litres of paint from, we'll calculate the cost at each store and compare.
Home Stores
Home Stores sells 2 litre tins at £4.75 each. To get 10 litres, Carly would need 5 tins:
5 tins × £4.75 = ¤23.75
Paint Supplies
Paint Supplies has a 3 for 2 offer, meaning for every three tins purchased, the third is free. Carly needs 10 tins (10 litres), so she would pay for 7 (because of the three sets of 3 for 2) and get 3 free:
7 tins × £3.90 = £27.30
The DIY Shop
The DIY shop offers 2.5 litre tins at £7.50 each, with a buy 3 get 1 free offer. Carly would need 4 tins to get 10 litres, but she would only have to pay for 3 tins:
3 tins × £7.50 = £22.50
Comparing the totals, Carly should buy her paint from The DIY shop because it offers the lowest price for 10 litres of paint, which costs £22.50.