Question

7. -1.25 points TanFin10 7.3.043. 0/6 Submissions Used My NOUS The following table gives the percentage of music downloaded from the United States and other countries by U.S. users: Country U.K Other U.S. Germany Canada Italy France Japan Percent 45.0 16.0 7.3 6.5 4.3 4.0 2.9 14.0 (a) Verify that the table does give a probability distribution for the experiment. The sum of the percents is %, so this does give a probability distribution. (b) What is the probability that a U.S. user who downloads music, selected at random, obtained it from either the United States or Canada? (Enter your answer to three decimal places.) (c) What is the probability that a U.S. user who downloads music, selected at random, does not obtain it from Italy, the United Kingdom (U.K.), or France? (Enter your answer to three decimal places.) My Notes O-1.25 points TanFin107.3.047. 0/6 Submissionss Used A poll was conducted among 250 residents of a certain city regarding tougher gun-control laws. The results of the poll are shown in the table. (Enter your answers to three decimal places.) Own Own Own a Handgun Own Only a Handgun Only a Rifle and a Rifle Neither Total 15 C 135 150 Favor Tougher Laws Oppose Tougher Laws No Opinion C 54 22 C 85 C C C 15 15 54 24 22 150 250 Total (a) If one of the participants is selected at random, what is the probability that he or she favors tougher gun-control laws? (b) If one of the participants is selected at random, what is the probability that he or she owns a handgun? (c) If one of the participants is selected at random, what is the probability that he or she owns a handgun but not a rifle? (d) If one of the participants is selected at random, what is the probability that he or she favors tougher gun-control laws and does not own a handgun?

Answer 1

(A)

Sum of percentages is

45167.3 +6.54.3+4+2.914.0 100

Since sum of percentages is 100 so given distribution is a valid probability distribution.

(B)

The required probability is

45.0 + 7.3 = 52.3 %

Answer: 0.523

(C)

From table we have

P(Italy) = 0.065

P(U.K) = 0.043

P(France) = 0.040

The required probability is

1 - 0.065 - 0.043 - 0.040 = 0.852

Answer : 0.852