l. A market study suggests that shoppers at a particular large department store spend an average of $36 per shopping trip. The variability in the distribution of purchase amounts is measured by the standard deviation of $12. If during a particular morning 42 shoppers will make purchases at the store, what is the probability that the total purchases will be below $1,450? What do I know? What do I want to find out? What do we expect the answer to be? How do I go from what I know to what I want to nd? Is the answer consistent with what I expected