practice 5 cj stats

CJ 317 Criminal Justice Statistics

Chapter 5 Practice

Work must be submitted as a Word or PDF document.  To show work, take a clear photo of your work, copy and paste it into the Word document prior to submission.   Any other submission will not be graded. 

A scientist is interested in the effect of time spent with parents and the number of hours youth spend watching television. The researcher knows that the average teen whose parents work outside the home spends 20 hours a week watching television. The population mean = 20 and the standard deviation of the distribution is equal to 5. Calculate the z-scores for the following individual times: Show work.

1. If X = 10, z = __________.

2. If X = 15, z = __________.

3. If X = 37, z = __________.

Use Table A in the textbook when necessary – also posted on BB under Course Documents/ Tables.

4. The percent of area beyond z = 1.44 is __________.

5. The percent of area between the z = 1.40 and z = 1.49 is __________.

6. The percent of TOTAL cases that have a z score less than or equal to 1.46 is __________.

7. The probability of obtaining a score between z = -1.40 and the mean is __________.

8. The percent of area between the mean and z = 1.45 is __________.

Problems – Show work

A criminal defense attorney is awaiting jury verdicts for three clients. A researcher predicts the chance of a guilty verdict is 20 percent chance for client 1, 30 percent for client 2, and 40 percent for client 3.

9. Calculate the probability that client one is found NOT guilty

10. Calculate the probability of a guilt-free verdict for all three clients.

11. Calculate the probability of verdicts at the end of week being, Client 1-guilty, Client 2-innocent, Client 3-guilty.

12. Calculate the probability of three guilty verdicts.

13. Calculate the probability of a guilty verdict for client 1, 2 OR 3.