Question

In: Statistics and Probability

There was an SRS of 100 flights on a large airline (airline 1) that showed that...

There was an SRS of 100 flights on a large airline (airline 1) that showed that 64 of the flights were on time. An SRS of 100 flights of another large airline (airline 2) showed that 80 of the flights were on time. Let p1 and p2 be the proportion of all flights that are on time for these two airlines.

What is a 95% confidence interval for the difference p1-p2?

(-.222, -.098)

(-.263, -.057)

(-.218, -.102)

(-.283, -.038)

(.098, .222)

Solutions

Expert Solution

Solution :

Given that,

= x1 / n1 = 64 / 100 = 0.64

1- = 0.36

= x2 / n2 = 80 / 100 = 0.80

1 - = 0.20

At 95% confidence level the z is ,

Z/2 = 1.96

95% confidence interval for p1 - p2 is ,

( - )   Z/2  * [(1- ) / n1 + (1 - ) / n2]

(0.64 - 0.80)   1.96 * [(0.64 * 0.36 ) / 100 + (0.80 * 0.20) / 100]

-0.283 < p1 - p2 < -0.038

(-0.283 , -0.038)


Related Solutions

An SRS of 100 flights of a large airline (call this airline 1) showed that 64...
An SRS of 100 flights of a large airline (call this airline 1) showed that 64 were on time. An SRS of 100 flights of another large airline (call this airline 2) showed that 80 were on time. Let p1 and p2 be the proportion of all flights that are on time for these two airlines. Reference: Ref 8-10 You wish to determine whether there is evidence of a difference in the on-time rate for the two airlines? To determine...
A simple random sample of 100 flights of a large airline (call this airline 1) showed...
A simple random sample of 100 flights of a large airline (call this airline 1) showed that 64 were on time. A simple random sample of 100 flights of another large airline (call this airline 2) showed that 80 were on time. Let p1 and p2 be the proportion of all flights that are on time for these two airlines. 21.Suppose we wish to conduct the test at a 10% significance level. What would our decision be? Based on that...
Eighty percent of flights arriving in Atlanta for a large US airline are on time. If...
Eighty percent of flights arriving in Atlanta for a large US airline are on time. If the FAA randomly selects 50 of the airline's flights, find the probability that: a. at least 85% of the sampled flights will be on time. b. at most 70% of the sampled flights will be on time. c. between 75% and 85% of the sampled flights will be on time.
In a large population, 46% of the households own VCR’s. A SRS of 100 households is...
In a large population, 46% of the households own VCR’s. A SRS of 100 households is to be contacted and asked if they own a VCR. a. Let p^ be the sample proportion who say they own a VCR. find the mean of the sampling distribution of the sample proportion b. Let p^ be the sample proportion who say they own a VCR. Find the standard deviation of the sampling distribution of the sample proportion c. Let p^ be the...
Unoccupied seats on flights cause airlines to lose revenue. Suppose a large airline wants to determine...
Unoccupied seats on flights cause airlines to lose revenue. Suppose a large airline wants to determine of the mean number of unoccupied seats on all its flights is greater than 10. To accomplish this, the records of 60 flights are randomly selected and the number of unoccupied seats is noted for each of the sampled flights. The sample mean is 11.4 seats and the sample standard deviation is 3.4 seats. Test the claim that mean number of unoccupied seats on...
Unoccupied seats on flights cause airlines to lose revenue. Suppose a large airline wants to determine...
Unoccupied seats on flights cause airlines to lose revenue. Suppose a large airline wants to determine of the mean number of unoccupied seats on all its flights is greater than 10. To accomplish this, the records of 60 flights are randomly selected and the number of unoccupied seats is noted for each of the sampled flights. The sample mean is 11.2 seats and the sample standard deviation is 3.4 seats. Test the claim that mean number of unoccupied seats on...
Unoccupied seats on flights cause airlines to lose revenue. Suppose a large airline wants to determine...
Unoccupied seats on flights cause airlines to lose revenue. Suppose a large airline wants to determine of the mean number of unoccupied seats on all its flights is greater than 10. To accomplish this, the records of 60 flights are randomly selected and the number of unoccupied seats is noted for each of the sampled flights. The sample mean is 11.2 seats and the sample standard deviation is 3.4 seats. Test the claim that mean number of unoccupied seats on...
Unoccupied seats on flights cause airlines to lose revenue. Suppose a large airline wants to estimate...
Unoccupied seats on flights cause airlines to lose revenue. Suppose a large airline wants to estimate its average number of unoccupied seats per flight over the past year. Two hundred and twenty-five flight records are randomly selected and the number of unoccupied seats is noted, with a sample mean of 11.6 seats and a population standard deviation of 4.1 seats. How many flights should we select if we wish to estimate μ to within 5 seats and be 95 percent...
Unoccupied seats on flights cause airlines to lose revenue. Suppose a large airline wants to determine...
Unoccupied seats on flights cause airlines to lose revenue. Suppose a large airline wants to determine of the mean number of unoccupied seats on all its flights is greater than 10. To accomplish this, the records of 60 flights are randomly selected and the number of unoccupied seats is noted for each of the sampled flights. The sample mean is 11.4 seats and the sample standard deviation is 3.4 seats. Test the claim that mean number of unoccupied seats on...
A. According to an airline, flights on a certain route are NOT on time 15% of...
A. According to an airline, flights on a certain route are NOT on time 15% of the time. Suppose 10 flights are randomly selected and the number of NOT on time flights is recorded. Find the probability of the following question. At least 3 flights are not on time. B. According to an airline, flights on a certain route are NOT on time 15% of the time. Suppose 10 flights are randomly selected and the number of NOT on time...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT