Assume that a simple random sample has been selected from a
normally distributed population and test the given claim. Identify
the null and alternative hypotheses, test statistic, P-value, and
state the final conclusion that addresses the original claim.
A simple random sample of 25 filtered 100 mm cigarettes is
obtained, and the tar content of each cigarette is measured. The
sample has a mean of 18.8 mg and a standard deviation of 3.63 mg.
Use a 0.05 significance level to test the claim that the mean tar
content of filtered 100 mm cigarettes is less than 21.1 mg, which
is the mean for unfiltered king size cigarettes. What do the
results suggest, if anything, about the effectiveness of the
filters?
a. test statistic=
b. pvalue =
c. State the final conclusion that addresses the original
claim.
d. What do the results suggest, if anything, about the
effectiveness of the filters?
2.
In a study of pregnant women and their ability to correctly predict
the sex of their baby, 59 of the pregnant women had 12 years of
education or less, and 39% of them correctly predicted the sex of
their baby. Use a 0.05 significance level to test the claim that
these women have no ability to predict the sex of their baby, and
the results are not significantly different from those that would
be expected with random guesses. Identify the null hypothesis,
alternative hypothesis, test statistic, P-value, conclusion about
the null hypothesis, and final conclusion that addresses the
original claim. Use the P-value method. Use the normal
distribution as an approximation of the binomial distribution.
a. test statistic=
b. pvalue=
c. Identify the conclusion about the null hypothesis and the final
conclusion that addresses the original claim.
3.
1997, a survey of 900 households showed that 147 of them use
e-mail. Use those sample results to test the claim that more than
15% of households use e-mail. Use a 0.05 significance level. Use
this information to answer the following questions.
a. test statistic=
b. pvalue=
c. what is the conclusion?
d. Is the conclusion valid today? Why or why not?
4.
In a survey of 150 senior executives, 46.7% said that the most
common job interview mistake is to have little or no knowledge of
the company. Use a 0.01 significance level to test the claim that
in the population of all senior executives, 40% say that the most
common job interview mistake is to have little or no knowledge of
the company. Identify the null hypothesis, alternative
hypothesis, test statistic, P-value, conclusion about the null
hypothesis, and final conclusion that addresses the original claim.
Use the P-value method. Use the normal distribution as an
approximation of the binomial distribution.
a. test statistic=
b. pvalue=
c. Identify the conclusion about the null hypothesis and the final
conclusion that addresses the original claim.