The lengths of the songs available for download on a website are normally distributed, with a mean length of 188 seconds, and a standard deviation of 24 seconds. Xavier downloaded a song with a length of 170 seconds. To the nearest tenth of a percent, Xavier's song is shorter than what percent of the songs available for download on the website?

The birth weights of children born in the United States are normally distributed and have a ?=7.5μ=7.5 pounds.  How does the median birth weight compare to the average birth weight?

On a nationwide math test, the mean was 57 and the standard deviation was 4. If Roberto scored 90, what was his z-score?

The average chef at a restaurant earns $17 an hour with a deviation of $1.75. What are the chances that someone is earning more than $20 an hour?

Skye High School has a total of 500 graduates.  The mean SAT score of Skye High School graduates is 947 with a standard deviation of 205.  To get into a premier college, a student must score 1000 or more.  If 60 students are selected at random, how many graduates can Skye High School expect to get into a premier college?

The heights of all women in the United States are known to be normally distributed with a mean of 63 inches and standard deviation of 3 inches. The U.S. Navy requires that fighter pilots have heights between 58 inches and 72 inches. Find the percentage of women in the United States that meet this height requirement. Round the solution to two decimal places, if necessary.

The Acme Company manufactures widgets. The distribution of widget weights is bell shaped. The widget have a mean of 40 ounces and a standard deviation of 10 ounces. What percentage of the widget weights lie between 20 and 70 ounces?

Max scored an 80 on her psychology quiz, but the class as a whole averaged a 40. If the standard deviation was 10, what was Alicia's z-score?

On a multiple choice test with 10 questions, each question has four possible answers, one of which is correct. For students who guess at all answers, find the standard deviation for the number of correct answers.

According to the U.S. Census, the average adult woman is the United States is 65 inches tall and the standard deviation is 3 inches.  If Zsike is 67 inches tall, what is her z-score?