BROWSE RESOURCES

# Study Quiz The Normal Distribution

Mathematics of Data Management 12 > Student Centre > Chapter 8 > Study Quiz The Normal Distribution

## Preview Study Quiz The Normal Distribution

Question 1
Marks: --/1
Which of the following would be likely to follow a uniform distribution?
 a. the waiting time to check out at a grocery store b. selection of a student by drawing a name from a hat c. driving times to work d. the sum on a roll of two dice
Question 2
Marks: --/1
The following waiting times and frequencies were recorded for customers checking out at a grocery store:Select an appropriate distribution, and determine the mean waiting time in minutes.
 a. 4 b. 1 c. 2 d. 8
Question 3
Marks: --/1
The time taken to clean up the Mt. Etna Pizza Parlour after it closes follows a normal distribution with a mean of 30 min and a standard deviation of 5 min. What is the probability that the cleanup crew will complete the job in less than 20 min?
 a. 0.500 b. 0.023 c. 0.977 d. 0.011
Question 4
Marks: --/1
The students applying to a computer engineering program at a university have a mean average of 85 with a standard deviation of 6. The admissions committee will only consider students in the top 20%. What cut-off mark should the committee use?
 a. 90 b. 79 c. 91 d. 80
Question 5
Marks: --/1
The refractive error, in diopters, of a sample of 20 students in a school is shown below.Assuming a normal distribution, and using the sample mean and standard deviation, estimate the probability that a student will have a refractive error of less than –1 or greater than +1, and hence will require corrective lenses.
 a. 0.616 b. 0.0983 c. 0.325 d. 0.291
Question 6
Marks: --/1
An advertisement for jelly beans claims "At least 100 beans in every box.". The machine used to fill the boxes has been found to fill boxes with a mean of 108 beans and a standard deviation of 3 beans. What is the probability that the advertising claim is true?
 a. 0.996 b. 0.994 c. 0.500 d. 0.998
Question 7
Marks: --/1
A company that makes digital watches finds that 2% of its watches fail within the warranty period and must be replaced. The company has sold a shipment of 10 000 watches to a major retail chain store. Use the normal approximation to the binomial distribution to determine the probability that 300 or more watches from this shipment will fail.
 a. 0.9936 b. 0.0064 c. 0.9938 d. 0.0062
Question 8
Marks: --/1
A model of engine used in small aircraft has a mean life of 2000 h of operation with a standard deviation of 100 h. Each year the engine manufacturer collects data on the life of 100 engines. What is the mean and the standard deviation of these samples?