In order to solve this problem, we need to find out how much 1 sweater costs before we can find out how much 9 sweaters costs. In order to find out how much 1 sweater costs, we have to divide the cost of 2 sweaters ($20.28) by 2 ($20.28 divided by 2). This gives us $10.14 for 1 sweater. Now that we know how much one sweater costs, we can find out how much 9 sweaters costs. To do this, simply multiply $10.14 by 9 (which gives us $91.26).
So, the answer to this question is that 9 sweaters costs $91.26.
