1. Which of the following are requirements of a random sample? a. Every individual has an equal chance of being selected. b. The probabilities cannot change during a series of selections. c. There must be sampling with replacement. d. There must be at least 100 observations. - Answer: A 2. A jar contains 10 red marbles and 30 blue marbles. What is the probability of randomly selecting a red marble from the jar? a. 10/30 b. 10/40 c. 1/10 d. 1/40 - Answer: B 3. A jar contains 10 red marbles and 30 blue marbles. A random sample without replacement of n=3 marbles is Probability and Sampling, Intro to Hypothesis Testing Chapter 6, 7, 8, selected from the jar. If the first two marbles are both blue, what is the probability that the third marble will be red? a. 10/37 b. 10/38 c. 10/40 d. 8/38 - Answer: B 4. What proportion of a normal distribution is located in the tail below z=2.00? a. 0.9772 b. 0.0228 c. 0.4772 d. 0.0456 - Answer: B 5. What proportion of a normal distribution is located in the tail beyond z=-1.00? a. 0.8413 b. 0.1587 c. 0.3413 d. 0.1587 - Answer: B Probability and Sampling, Intro to Hypothesis Testing Chapter 6, 7, 8, 6. What proportion of a normal distribution is located between the mean and z= 1.40? a. 0.9192 b. 0.0808 c. 0.4192 d. 0.8384 - Answer: C 7. What proportion of a normal distribution is located between the mean and z=-0.40? a. 0.6554 b. 0.3446 c. 0.1554 d. 0.3108 - Answer: C 8. A vertical line is drawn through a normal distribution at z=0.50 and separates the distribution into two sections. What the proportion of the distribution is in the larger section? a. 0.6915 b. 0.3085 c. 0.1915 d. 0.3830 - Answer: A