Exam 7: Continuous Probability Distributions

What proportion of the area under a normal curve is to the left of z = 0.50? ________

What is an important similarity between the uniform and normal probability distributions?

The seasonal output of a new experimental strain of pepper plants was carefully weighed. The mean weight per plant is 15.0 pounds, and the standard deviation of the normally distributed weights is 1.75 pounds. Of the 200 plants in the experiment, how many produced peppers weighing between 13 and 16 pounds?

The weight of a bag of corn chips is normally distributed with a mean of 22 ounces and a standard deviation of ½ ounces. What is the probability that a bag of corn chips weighs more than 21 ounces? _____

What is the area under the normal curve between z = 0.0 and z = 1.79?

After arriving at the university student medical clinic, the waiting times to receive service after checking-in follow an exponential distribution with a mean of 10 minutes. Calculate the probability a student waits more than 12 minutes.

Two business major students, in two different sections of an economics class, were comparing test scores. The following gives the students scores, class mean, and standard deviation for each section. Which student scored better compared to the rest of the section? _______________

The exponential distribution is applied to situations characterized by _______.

A random variable from an experiment where outcomes are normally distributed

The mean of any uniform probability distribution is

A binomial distribution has 100 trials (n = 100) with a probability of success of 0.25 ( $\pi$ =0.25). We would like to find the probability of 75 or more successes using the normal distribution to approximate the binomial. Applying the continuity correction factor, what value would be used to calculate a z-score?

A binomial distribution has 100 trials (n = 100) with a probability of success of 0.25 ( $\pi$ =0.25). To apply the normal distribution to approximate the binomial, what are the mean and standard deviation?

What is the percentage of the total area under the normal curve within plus and minus two standard deviations of the mean?

From past history, the scores on a statistics test are normally distributed with a mean score of 70 and a standard deviation of 5. To earn a "C" on the test, a student must be in the top 25% of the class. What should a student score to receive a "C"? _______

What is the formula to convert any normal distribution to the standard normal distribution? _______________________

A national manufacturer of unattached garages discovered that the distribution of the lengths of time it takes two construction workers to erect the Red Barn model is normally distributed with a mean of 32 hours and a standard deviation of 2 hours. What percent of the garages take between 32 and 34 hours to erect?

In a uniform distribution, probabilities are represented by ___________.

The mean score of a college entrance test is 500; the standard deviation is 75. The scores are normally distributed. What percent of the students scored below 320?

What happens to the shape of a binomial distribution as the number of trials increases? ________________

In the exponential distribution, the mean and standard deviation are equal to ______________