A recent Internet survey showed per-day lodging expenses at Disney World in Orlando range from less than $100 for a campsite to more than $2,000 for a top luxury room. The cost-per-day average of the top 10 most popular hotels at Disney World is $348.
a. If the standard deviation is $80, find the z-score for a per-day expense of $400.
b. If the data are approximately normally distributed with mean $348 and standard deviation $80, what percent of the hotels have per-day expenses greater than $268?