Originally Posted by

**patrick915** I need help with these questions....

1. Correctly state the null and alternative hypothesis for the following problem situations.

(a) The average time a patrolman spends filling out reports is 2.34 hours per day.

(b) A person, on average, will receive 4.83 speeding tickets in their lifetime.

(c) The Police Department qualifies at least 94% of its officers on new CPI

techniques.

2. Explain why the more “tests” you run on a certain hypothesis the closer your sampling

average should come to the population average. (i.e. explain how the CLT works)

3. A manufacturer claims that the life of a gun barrel on their standard-issue 9mm is 2,540

shots with a standard deviation of 93 shots. A random sample of 100 guns is collected

and it is found that the average lifespan of their barrels is 2,514. Using the .02 confidence

level, is this collection of guns significantly below manufacturing standards?

4. According to the U.S. Department of Justice, in 1992 the average convicted rapist was

sentenced to 117 months in prison. The average time served was only 65 months. If you

were to collect a random sampling of 50 convicted rapists in Ohio and found the average

time they served was 70.43 months, would this be sufficient information to state that

prisoners in Ohio serve sentences sufficiently greater than the national average?

(Use á = .01 & ó = 12.34)

5. Using the hypothesis from problem (1), correctly report the results if. . . . .

(a) Your experiment found the average patrolman spent 2.50 hours per day filling

out reports.

(b) You poll 50 people and find they have gotten an average of 1.93 speeding

tickets per person.

(c) The Police Department qualified 98% of its officers.