Normal Distributions Answers

Suppose that the heights of adult women are normally distributed with = 65 inches and = 2.5 inches. Find the probability that a randomly chosen woman is taller than 65 inches.

Daytime high temperatures in New York in February are normally distributed with an average of 30.2º and a standard deviation of 8.5º.Estimate the probability that the temperature on a given day in February is 39º or higher.

A normal distribution is bell-shaped and symmetric about its mean.

A set of data is normally distributed with a mean of 455 and a standard deviation of 25. What percent of the data is in the interval 405–455?

In a certain normal distribution of scores, the mean is 30 and the standard deviation is 3. Find the z-score corresponding to a score of 23.

A set of data is normally distributed with a mean of 75 and a standard deviation of 3. What percent of the data is in the interval 72–78?

The heights of 1000 students at a local school were recorded and found to be approximated by the normal curve below. Which answer could represent the mean and standard deviation for these data?

A sample of restaurants in a city showed that the average cost of a glass of iced tea is $1.25 with a standard deviation of 7¢. If a new restaurant charges a price for iced tea that has a z-value of -1.25, then what is the tea’s actual cost?

In a certain normal distribution of scores, the mean is 40 and the standard deviation is 3. Find the z-score corresponding to a score of 54.

A set of data is normally distributed with a mean of 28 and a standard deviation of 2. What is the probability that a value from the data is less than 22 or greater than 34?