> Need help with these word problems, pretty hard. If you know the DEFINITIONS, they are actually pretty easy.
> > 1. Airline Delays. Suppose you are a scheduler for a > major airline, analyzing a distribution of flight > delays (departures) during one day at an airport. The > distribution of delay times has the following > properties: The mean delay is 10 minutes, the median > delay is 6 minutes, the mode is the distribution is 0 > minutes, and the maximum delay is 25 minutes. > > a. What percentage of flights were delayed less than > 6 minutes? > > b. What percentage of flights were delayed more than > 6 minutes? > Do you know what "median" means? If you do, then these two questiohs are trivial.
> 2. Body Mass Index (BMI). The body mass indices of > American men between ages 30 and 50 are normally > distributed with a mean of 26.2 and a standard > deviation of 4.7. > > a. Determine the standard score and percentile of a > BMI of 22. > Given a normal distribution with mean m and standar deviation s, the "standard normal variable corresponding to variable x is z= (x- m)/s.
> b. Determine the standard score and percentile of a > BMI of 28. > Same thing. z= (26- 26.2)/4.7
> c. Several health organizations have declared that > men with a BMI of 25 or greater are overweight and > that men with a BMI of 30 or greater are obese. What > percentage of American men are overweight? obese? z= (26- 26.2)/4.7. Look that up on a table