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In a survey taken 10 years ago, it was found that 10% of customers of a supermarket brought along their own shopping bags. A recent survey aimed to prove that the current percentage of customers bringing along their own shopping bags is different from 10%. In the survey, it was found that 92 of the 1 000 customers surveyed brought along their own shopping bags. We want to test the claim that the current percentage is not 10%, at the 5% significance level
(a) State the appropriate null and alternative hypothesis.
(b) State and calculate the appropriate test statistic.
(c) Determine the critical value of the test or the p–value of the test.
(d) State whether or not you reject the null hypothesis, giving the reason.
(e) Draw an appropriate conclusion
Amilkprocessing company testimplementedaplant-wide energy conservation programwitha goal of reducing themeandaily consumptionrateof atleast 1,000kWhfromitsnormaloperatingplants.The conservationprogramwas implementedinPlant B.The following data was collected on weekdays where consumption level is atits peak.Were the conservation efforts effective in achieving its goal? Compare the results with Plant A’s data where the program is not implemented using 𝛼 = 0.05. Assume that the population variances arenot equal. Plant A (kWh) Plant B (kWh) 3,952.80 4,036.00 3,276.00 4,036.00 3,636.00 4,036.00 3,636.00 3,264.00 3,636.00 864.00 3,636.00 1,368.00 4,068.00 2,196.00 4,068.00 4,392.00 4,362.00 5,220.00 4,362.00 3,600.00 4,362.00 3,960.00 4,362.00 4,428.00 3,882.00 756.00 3,808.80 612.00 3,808.80 684.0
In order to know the age at which student smokers started smoking, 15 randomly selected students
smokers about the age they started smoking. The results is shown below.
21 17 20 19 16 15 17 18 25 24 19 16 22 19 23
(a) Using the sign test and the critical region method, test at 10% significance level the
hypothesis that the third quartile is 20 years.
(b) Use to the Wilcoxon Signed Rank test to test at 10% level of significance whether the median
age is less than 19 years.
Which of the options is the rejection region for testing H0: μ = 100 vs. H1: μ ¹ 100, at the 0.05 level of significance?Select one:
a. | z | < 0.95
b. | z | > 1.96
c. z > 1.65
d. z < 2.33
If you want to carry out a statistical test at α = 0.01. to test whether the population mean is equal to 500 or not, using a sample size of 300, with a test statistic of z = 1.97, your conclusion should be_____.Select one:
a. do not reject the null hypothesis
b. reject the null hypothesis
c. only reject when the test statistic is negative
d. not enough information to determine
The confidence interval is 0.35 < p < 0.45. The claimed value of p = 0.42. What is the decision? Select one:
a. Reject the null hypothesis
b. Support the null hypothesis
c. Retain the null Hypothesis
d. Support the alternative hypothesis
The confident interval is 0.25 < p < 0.45. The claimed value is p = 0.50 What is the decision? Select one:
a. Retain the null hypothesis
b. Support the null hypothesis
c. Reject the null hypothesis
d. Support the alternative hypothesis
The test statistic is z = 0.86, the critical value is z = 1.645. This is a________.Select one:
a. A and B
b. Two tail test
c. Left tail test
d. Right tail test
In confidence interval estimation, formula of calculating confidence interval is_______. Select one:
a. point estimate + margin of error
b. point estimate * margin of error
c. point estimate - margin of error
d. point estimate ± margin of error
