a) Tim is tiling a wall and needs to buy at least 100 tiles. The tiles are sold in large packs and small packs. Large pack 40 tiles 17 Small pack 26 tiles 12 Special offer 25% reduction when you buy 3 or more large packs Work out the cheapest cost to buy the packs of tiles he needs. Your final line must say, Cheapest cost = ... When you earn money you pay income tax. The amount you pay depends on how much you earn that year. You pay 0% on the first 12 500 you earn 20% on the next 37500 you earn 40% on the next 112 500 you earn One year, Sam paid 13 150 income tax. Work out how much he earned that year