The chief physician at a hospital wants to analyze the amount of time it takes two doctors to complete a particular surgical procedure. A sample of 40 of these procedures performed by Dr. McCoy were completed in a mean time of 70.8 minutes with a standard deviation of 1.5 minutes. A sample of 35 these procedures performed by Dr. Turk were completed in a mean time of 71.4 minutes with a standard deviation of 2.4 minutes. A claim is made that the mean time for Dr. McCoy ( μ 1 μ1 ) is less than the mean time for Dr. Turk ( μ 2 μ2 ). For each part below, enter only a numeric value in the answer box. For example, do not type "z =" or "t =" before your answers. Round each of your answers to 3 places after the decimal point.
(a) Calculate the value of the test statistic used in this test. Test statistic's value =
(b) Use your calculator to find the P-value of this test. P-value =
The chief physician at a hospital wants to analyze the amount of time it takes two...
We need to examine the difference in the average time it takes two different passenger trains to complete a certain route. The standard deviations of these populations are unknown, but they are assumed to be equal to each other. A sample of 41 routes that were run by American Railways had a mean of 76 minutes and standard deviation of 4.1 minutes. A sample of 32 routes that were run by Midwest Railways had a mean of 75.2 minutes and...
Government regulators need to analyze the distance that two brands of electric cars can be driven between charges. A sample of 39 Lincomb Auto Company electric vehicles could drive a mean distance of 75.9 miles with a standard deviation of 4.1 miles. A sample of 38 Shevroley Auto Company electric vehicles could drive a mean distance of 74.3 miles with a standard deviation of 3.4 miles. A claim is made that the mean distance for Lincomb vehicles (μ1) is greater...
We will analyze the difference in the fuel efficiency of two new brands of hybrid vehicles. The standard deviations of these two populations are unknown, but the engineers from these companies believe that they are equal. A sample of 38 hybrid vehicles produced by Forde Motors had a mean of 70.3 MPG and standard deviation of 1.6 MPG, and a sample of 33 hybrid vehicles produced by GeM motors had a mean of 69.7 MPG and standard deviation of 4.9 MPG....
A phone manufacturer wants to compete in the touch screen phone market. Management understands that the leading product has a less than desirable battery life. They aim to compete with a new touch screen phone that is guaranteed to have a battery life more than two hours longer than the leading product. A recent sample of 120 units of the leading product provides a mean battery life of 5 hours and 40 minutes with a standard deviation of 30 minutes. A...
Suppose the national average dollar amount for an automobile insurance claim is $788.5. You work for an agency in Michigan and you are interested in whether or not the state average is greater than the national average. The hypotheses for this scenario are as follows: Null Hypothesis: μ ≤ 788.5, Alternative Hypothesis: μ > 788.5. You take a random sample of claims and calculate a p-value of 0.0851 based on the data, what is the appropriate conclusion? Conclude at the...
A phone manufacturer wants to compete in the touch screen phone market. Management understands that the leading product has a less than desirable battery life. They aim to compete with a new touch screen phone that is guaranteed to have a battery life more than two hours longer than the leading product. A recent sample of 123 units of the leading product provides a mean battery life of 5 hours and 50 minutes with a standard deviation of 41 minutes....
You may need to use the appropriate technology to answer this question. Researchers at two universities found that airlines are doing a better job of getting passengers to their destinations on time. Company A and Company B Airlines were among the leaders in on-time arrivals with both having 88% of their flights arriving on time. But for the 12% of flights that were delayed, how many minutes were these flights late? Sample data showing the number of minutes that delayed...
A random sample of 50 students is selected and it is found that the mean of daily internet usage is 70.8 minutes with standard deviation of 13.8 minutes. A hypothesis test was performed to determine whether the true mean usage, µ equal to 72.0 minutes or not. What is the p-value of the test?
An experiment was planned to compare the mean time (in days) required to recover from a common cold for persons given a daily dose of 4 mg of vitamin C, μ2, versus those who were not given a vitamin supplement, μ1. Suppose that 34 adults were randomly selected for each treatment category and that the mean recovery times and standard deviations for the two groups were as follows. No Vitamin Supplement 4 mg Vitamin C Sample size 34 34...
A comparison is made between two bus lines to determine if arrival times of their regular buses from Denver to Durango are off schedule by the same amount of time. For 51 randomly selected runs, bus line A was observed to be off schedule an average time of 53 minutes, with standard deviation 19minutes. For 61 randomly selected runs, bus line B was observed to be off schedule an average of 62 minutes, with standard deviation 15 minutes. Do the...