A coffee manufacturer is interested in whether the mean daily consumption of regular-coffee drinkers is less than that of decaffeinated-coffee drinkers. Assume the population standard deviation for those drinking regular coffee is 1.27 cups per day and 1.42 cups per day for those drinking decaffeinated coffee. A random sample of 51 regular-coffee drinkers showed a mean of 4.28 cups per day. A sample of 47 decaffeinated-coffee drinkers showed a mean of 5.50 cups per day.
Use the .01 significance level.
1.
This is a -tailed test.
2.
The decision rule is to reject H0: μr ≥ μd if z < . (Negative amount should be indicated by a minus sign. Round your answer to 2 decimal places.)
3.
The test statistic is z = . (Negative amount should be indicated by a minus sign. Round your answer to 2 decimal places.)
4.
What is your decision regarding H0 ?
5.
The p-value is
.
One of the music industry’s most pressing questions is: Can paid download stores contend nose-to-nose with free peer-to-peer download services? Data gathered over the last 12 months show Apple’s iTunes was used by an average of 1.65 million households with a sample standard deviation of .56 million family units. Over the same 12 months WinMX (a no-cost P2P download service) was used by an average of 2.20 million families with a sample standard deviation of .30 million. Assume the population standard deviations are not the same.
1.
Find the degrees of freedom for unequal variance test. (Round down your answer to nearest whole number.)
Degrees of freedom
2
State the decision rule for .05 significance level: H0: A = W; H1: A ≠ W . (Negative amounts should be indicated by a minus sign. Round your answer to 3 decimal places.)
Reject H0 if t < or t >
3.
Compute the value of the test statistic. (Negative amount should be indicated by a minus sign.Round your answer to 2 decimal places.)
Value of the test statistic
4.
Test the hypothesis of no difference in the mean number of households picking either variety of service to download songs. Use the .05 significance level.
H0. There is difference in the mean number of households picking either variety of service to download songs.
A recent study focused on the number of times men and women who live alone buy take-out dinner in a month. Assume that the distributions follow the normal probability distribution and the population standard deviations are not equal. The information is summarized below.
Statistic
Men
Women
Sample mean
25.17
22.50
Sample standard deviation
5.69
4.51
Sample size
34
36
At the .01 significance level, is there a difference in the mean number of times men and women order take-out dinners in a month?
1.
Compute the value of the test statistic. (Round your answer to 3 decimal places.)
Value of the test statistic
2.
What is your decision regarding on null hypothesis?
The decision is the null hypothesis that the means are the same.
3.
What is the p-value? (Round your answer to 4 decimal places.)
Chicken Delight claims that 94% of its orders are delivered within 10 minutes of the time the order is placed. A sample of 90 orders revealed that 82 were delivered within the promised time. At the 0.05 significance level, can we conclude that less than 94% of the orders are delivered in less than 10 minutes?
a.
What is the decision rule? (Negative amount should be indicated by a minus sign. Round your answer to 2 decimal places.)
Reject H0 if z <
b.
Compute the value of the test statistic. (Negative amount should be indicated by a minus sign. Round the intermediate values and final answer to 2 decimal places.)
Value of the test statistic
c.
What is your decision regarding the null hypothesis?
H0 : π ≥ 0.94
The Damon family owns a large grape vineyard in western New York along Lake Erie. The grapevines must be sprayed at the beginning of the growing season to protect against various insects and diseases. Two new insecticides have just been marketed: Pernod 5 and Action. To test their effectiveness, three long rows were selected and sprayed with Pernod 5, and three others were sprayed with Action. When the grapes ripened, 400 of the vines treated with Pernod 5 were checked for infestation. Likewise, a sample of 400 vines sprayed with Action were checked. The results are:
Insecticide
Number of Vines Checked (sample size)
Number of Infested Vines
Pernod 5
400
26
Action
400
39
At the .10 significance level, can we conclude that there is a difference in the proportion of vines infested using Pernod 5 as opposed to Action? Hint: For the calculations, assume the Pernod as the first sample.
1.
State the decision rule. (Negative amounts should be indicated by a minus sign.Do not round the intermediate values.Round your answers to 2 decimal places.)
H0 is rejected if z < or z > .
Compute the pooled proportion. (Do not round the intermediate values. Round your answer to 3 decimal places.)
Pooled proportion
2.
Compute the value of the test statistic. (Negative amount should be indicated by a minus sign.Do not round the intermediate values. Round your answer to 2 decimal places.)
Value of the test statistic
3.
What is your decision regarding the null hypothesis?
Decision
There are two major cell phone providers in the Colorado Springs, Colorado, area, one called HTC and the other, Mountain Communications. We want to investigate whether there is a difference in the proportion of times a customer is able to successfully access the Internet. During a one-week period, 500 calls were placed at random times throughout the day and night to HTC; 450 of the calls were successful. A similar one-week study with Mountain Communications showed that 352 of 400 calls were successful. At the .01 significance level, is there a difference in the percent of time that cell phone connections are successful?
State the null and alternate hypotheses.
Ho: πHTCπMountain
H1: πHTCπMountain
Make the decision rule. (Negative amounts should be indicated by a minus sign. Round your answers to 3 decimal places.)
Reject Ho if z is
and
.
Evaluate the test statistic. (Round your answer to 2 decimal places.)
Test statistic
What is the decision regarding the null hypothesis?
Ho is . difference in the percentages.
https://urgentassignments.com/wp-content/uploads/2020/07/logo-2-300x75.png00adminhttps://urgentassignments.com/wp-content/uploads/2020/07/logo-2-300x75.pngadmin2023-12-01 22:15:302023-12-01 22:48:56A coffee manufacturer is interested in whether the mean daily consumption of regular-coffee drinkers
