Question 15
Nam spends 20 dollars on 20 stationery items consisting of books, pens and pencils. Each book costs 3 dollars, each pen 1.5 dollars and each pencil 0.5 dollars. How many dollars does he spend on books?
Convention: Assume Nam buys at least one item of each of the three types.
Convention: Assume Nam buys at least one item of each of the three types.