20. New Home Prices If the average price of a new one- family home is $246,300 with a standard deviation of $15,000, find the minimum and maximum prices of the houses that a contractor will build to...

20.

New Home Prices
If the average price of a new one- family home is $246,300 with a standard deviation of

$15,000, find the minimum and maximum prices of the houses that a contractor will build to satisfy the middle 80% of the market. Assume that the variable is normally distributed.

Source:
New York Times Almanac.

21.

Cost of Personal Computers
The average price of a personal computer (PC) is $949. If the computer prices are approximately normally distributed and s = $100, what is the probability that a randomly selected PC costs more than $1200? The least expensive 10% of personal computers cost less than what amount?

Source:
New York Times Almanac.