Concept explainers
For Exercises 7 through 23, perform each of the following steps.
a. State the hypotheses and identify the claim.
b. Find the critical value(s).
c. Find the test value.
d. Make the decision.
e. Summarize the results.
Use the traditional method of hypothesis testing unless otherwise specified.
Assume that the population is approximately
7. Cigarette Smoking A researcher found that a cigarette smoker smokes on average 31 cigarettes a day. She feels that this average is too high. She selected a random sample of 10 smokers and found that the mean number of cigarettes they smoked per day was 28. The sample standard deviation was 2.7. At α = 0.05 is there enough evidence to support her claim?
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Chapter 8 Solutions
Elementary Statistics: A Step By Step Approach
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- Brown wants to conduct an assessment of where employees live and how employees work. Brown wanted to know if where you lived was related to how you worked. What hypothesis tests can be used in this case?arrow_forwardYou are given the following hypotheses H 0 :p=0.3 H A :p not equal 0.3 We know that the sample size 90. For what sample proportion would the pvalue be equal to 0.1? Assume that all conditions necessary for Inference are satisfied.arrow_forwardIf the proportion of the population in City A that is over 65 years old is p1 and the proportion of the population in City B that is over 65 years old is p2, what is the null hypothesis for a test to determine if the proportion of the population that is over 65 years old is greater in City A? Select the correct answer below: H0: p1−p2=0 H0: p1−p2>0 H0: p1−p2<0 H0: p1−p2≠0arrow_forward
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