Question

In: Statistics and Probability

The mean cost of domestic airfares in the United States rose to an all-time high of...

The mean cost of domestic airfares in the United States rose to an all-time high of $370 per ticket. Airfares were based on the total ticket value, which consisted of the price charged by the airlines plus any additional taxes and fees. Assume domestic airfares are normally distributed with a standard deviation of $120. Use Table 1 in Appendix B.

a. What is the probability that a domestic airfare is $550 or more (to 4 decimals)?

b. What is the probability that a domestic airfare is $245 or less (to 4 decimals)?

c. What if the probability that a domestic airfare is between $320 and $480 (to 4 decimals)?

d. What is the cost for the 5% highest domestic airfares? (rounded to nearest dollar)

Solutions

Expert Solution

a) P(X > 550)

= P((X - )/> (550 - )/)

= P(Z > (550 - 370)/120)

= P(Z > 1.5)

= 1 - P(Z < 1.5)

= 1 - 0.9332

= 0.0668

b) P(X < 245)

= P((X - )/< (245 - )/)

= P(Z < (245 - 370)/120)

= P(Z < -1.04)

= 0.1492

c) P(320 < X < 480)

= P((320 - )/ < (X - )/ < (480 - )/)

= P((320 - 370)/120 < Z < (480 - 370)/120)

= P(-0.42 < Z < 0.92)

= P(Z < 0.92) - P(Z < -0.42)

= 0.8212 - 0.3372

= 0.484

d) P(X > x) = 0.05

or, P((X - )/ > (x - )/) = 0.05

or, P(Z > (x - 370)/120) = 0.05

or, P(Z < (x - 370)/120) = 0.95

or, (x - 370)/120 = 1.645

or, x = 1.645 * 120 + 370

or, x = 567.4 = 567


Related Solutions

The mean cost of domestic airfares in the United States rose to an all-time high of...
The mean cost of domestic airfares in the United States rose to an all-time high of $385 per ticket (Bureau of Transportation Statistics website, November 2, 2012 ). Airfares were based on the total ticket value, which consisted of the price charged by the airlines plus any additional taxes and fees. Assume domestic airfares are normally distributed with a standard deviation of $110. a. What is the probability that a domestic airfare is $550 or more (to 4 decimals)? b....
The mean cost of domestic airfares in the United States rose to an all-time high of...
The mean cost of domestic airfares in the United States rose to an all-time high of $400 per ticket. Airfares were based on the total ticket value, which consisted of the price charged by the airlines plus any additional taxes and fees. Assume domestic airfares are normally distributed with a standard deviation of $120. Use Table 1 in Appendix B.   What is the probability that a domestic airfare is $530 or more (to 4 decimals)? b. What is the probability...
The mean cost of domestic airfares in the United States rose to an all-time high of...
The mean cost of domestic airfares in the United States rose to an all-time high of $400 per ticket. Airfares were based on the total ticket value, which consisted of the price charged by the airlines plus any additional taxes and fees. Assume domestic airfares are normally distributed with a standard deviation of $120. Use Table 1 in Appendix B. a. What is the probability that a domestic airfare is $560 or more (to 4 decimals)? b. What is the...
The mean cost of domestic airfares in the United States rose to an all-time high of...
The mean cost of domestic airfares in the United States rose to an all-time high of $385 per ticket. Airfares were based on the total ticket value, which consisted of the price charged by the airlines plus any additional taxes and fees. Assume domestic airfares are normally distributed with a standard deviation of $120. Use Table 1 in Appendix B. a. What is the probability that a domestic airfare is $560 or more (to 4 decimals)? b. What is the...
The mean cost of domestic airfares in the United States rose to an all-time high of...
The mean cost of domestic airfares in the United States rose to an all-time high of $375 per ticket. Airfares were based on the total ticket value, which consisted of the price charged by the airlines plus any additional taxes and fees. Assume domestic airfares are normally distributed with a standard deviation of $100. Use Table 1 in Appendix B. a. What is the probability that a domestic airfare is $540 or more (to 4 decimals)? b. What is the...
The mean cost of domestic airfares in the United States rose to an all-time high of...
The mean cost of domestic airfares in the United States rose to an all-time high of $385 per ticket.† Airfares were based on the total ticket value, which consisted of the price charged by the airlines plus any additional taxes and fees. Assume domestic airfares are normally distributed with a standard deviation of $110. (a) What is the probability that a domestic airfare is $561 or more? (Round your answer to four decimal places.) (b) What is the probability that...
The mean cost of domestic airfares in the United States rose to an all-time high of...
The mean cost of domestic airfares in the United States rose to an all-time high of $370 per ticket. Airfares were based on the total ticket value, which consisted of the price charged by the airlines plus any additional taxes and fees. Assume domestic airfares are normally distributed with a standard deviation of $100. Use Table 1 in Appendix B. a. What is the probability that a domestic airfare is $530 or more (to 4 decimals)? b. What is the...
The mean cost of domestic airfares in the United States rose to an all-time high of...
The mean cost of domestic airfares in the United States rose to an all-time high of $400 per ticket. Airfares were based on the total ticket value, which consisted of the price charged by the airlines plus any additional taxes and fees. Assume domestic airfares are normally distributed with a standard deviation of $115. Use Table 1 in Appendix B. a. What is the probability that a domestic airfare is $560 or more (to 4 decimals)? b. What is the...
The mean cost of domestic airfares in the United States rose to an all-time high of...
The mean cost of domestic airfares in the United States rose to an all-time high of $400 per ticket. Airfares were based on the total ticket value, which consisted of the price charged by the airlines plus any additional taxes and fees. Assume domestic airfares are normally distributed with a standard deviation of $105. Use Table 1 in Appendix B. a. What is the probability that a domestic airfare is $530 or more (to 4 decimals)? b. What is the...
The mean cost of domestic airfares in the United States rose to an all-time high of...
The mean cost of domestic airfares in the United States rose to an all-time high of $400 per ticket. Airfares were based on the total ticket value, which consisted of the price charged by the airlines plus any additional taxes and fees. Assume domestic airfares are normally distributed with a standard deviation of $100. Use Table 1 in Appendix B. a. What is the probability that a domestic airfare is $540 or more (to 4 decimals)? b. What is the...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT