SB - Chapter 6

If X is a discrete uniform random variable ranging from 0 to 12, find P(X ≥ 10).

• .1126

• .2500

• .2308

• .1666

If X is a discrete uniform random variable ranging from one to eight, find P(X < 6).

• .6250

• .7500

• .3750

• .5000

Which of the following characterizes a Bernoulli process?

• A random experiment that has only two outcomes.

• The "success" must be a desirable outcome.

• .Either outcome has the same chance of occurrence.

• The probability of "success" varies with each trial.

The expected value (mean) of a binomial variable is 25. The number of trials is 50. The probability of "success" is:

• .75

• .50

• .30

• .25

If 90 percent of automobiles in Orange County have both headlights working, what is the probability that in a sample of eight automobiles, at least seven will have both headlights working?

• .8131

• .3826

• .6174

• .1869

If 5 percent of automobiles in Oakland County have one burned-out headlight, what is the probability that, in a sample of 10 automobiles, none will have a burned-out headlight?

• .0116

• .3151

• .1872

• .5987

Based on experience, 60 percent of the women who request a pregnancy test at a certain clinic are actually pregnant. In a random sample of 12 women, what is the probability that at least 10 are pregnant?

• .0835

• .1424

• .0639

• .0196

Jankord Jewelers permits the return of their diamond wedding rings, provided the return occurs within two weeks. Typically, 10 percent are returned. If eight rings are sold today, what is the probability that fewer than three will be returned?

• .0331

• .9619

• .9950

• .1488

On a Sunday in April, dog bite victims arrive at Carver Memorial Hospital at a historical rate of 0.6 victim per day. On a given Sunday in April, what is the probability that exactly two dog bite victims will arrive?

• .0988

• .0919

• .0902

• .0875

If tubing averages 16 defects per 100 meters, what is the probability of finding exactly 2 defects in a randomly chosen 10-meter piece of tubing?

• .3422

• .2674

• .8795

• .2584