Aresearcher wishes to know, with 98% confidence, the percentage of women who wear shoes that are too small for their feet. a previous study conducted by the academy of orthopedic surgeons found that 80% of women wear shoes that are too small for their feet. if the researcher wants her estimate to be within 3% of the true proportion, how large a sample is necessary?

Anderson, a computer engineer, and spouse, who is unemployed, provide more than half of the support for their child, age 23, who is a full-time student and who earns $7,000. they also provide more than half of the support for their older child, age 33, who earns $2,000 during the year. how many dependents may the andersons claim on their joint tax return?

The school cafeteria can make pizza for approximately $0.30 a slice. the cost of kitchen use and cafeteria staff runs about $200 per day. the pizza den nearby will deliver whole pizzas for $9.00 each. the cafeteria staff cuts the pizza into eight slices and serves them in the usual cafeteria line. with no cooking duties, the staff can be reduced by half, for a fixed cost of $75 per day. should the school cafeteria make or buy its pizzas?

Noah met an old friend at a coffee shop. he jotted down the friend's new phone number, but later that afternoon he could not find it or remember what he had done with it. a couple of days later, noah went back to the coffee shop, and while waiting in line, he suddenly remembered where he had put the phone number. this is an example of: