1Claim: The mean test score is not 78. Test statistic: z = 2.05 A) 0.0202 B) 0.9596 C) 0.9798
z = 2.05
2 Determine the decision criterion for rejecting the null hypothesis in the given hypothesis
test; i.e., describe the values of the test statistic that would result in rejection of the null
hypothesis. The principal of a middle school claims that the mean test score of the seventhgraders at his school is higher than 72.1. You wish to test this claim at the 0.05 level of
significance. The mean score for a random sample of 101 seventh-graders is 75.7 with a
standard deviation of 15.2. What criterion would be used for rejecting the null hypothesis? A)
Reject H0 if test statistic < 1.66. B) Reject H0 if test statistic > 1.96. C) Reject H0 if test
statistic > 1.96 or < -1.96. D) Reject H0 if test statistic > 1.66.
D) Reject H0 if test statistic > 1.66.
3 Use the P-value method to test the given hypothesis and give the test statistic. The Maine
Department of Natural Resources reported that the mean weight of lobsters trapped in the
state is 1.7 pounds. Carl Lewis is a lobster trapper off the coast of Maine. Carl suspects that
this figure is too high so he records the weights of a random sample of 38 lobsters that he
trapped. If = 1.5 pounds and s = 0.6 pounds, use a 1 percent level of significance to test Carl's
claim that the mean weight is less than 1.7 pounds. A) The test statistics is t = -2.05. There's
not sufficient evidence to conclude that the mean is lower than 1.7 pounds. B) The test
statistics is t = -2.05. There is sufficient evidence to conclude that the mean is lower than 1.7
pounds. C) The test statistics is t = 2.06. There's not sufficient evidence to conclude that the
mean is lower than 1.7 pounds. D) The test statistics is t = 2.06. There is sufficient evidence
to conclude that the mean is lower than 1.7 pounds.
A) The test statistics is t = -2.05. There's not sufficient evidence to conclude that the
mean is lower than 1.7 pounds
Find the critical t value or values for the given hypothesis, sample size, and significance
level. H1: µ ? 2.3 n = 6 a = 0.01 A) ±4.032 B) ±3.143 C) ±3.365
A) ±4.032
Should the statistician use a t distribution, a normal distribution, or neither to test the null
hypothesis? A series of measurements on a machine part yielded the following sample
statistics. The series was normally distributed. A sample is taken and the mean for the data set
is 9.19, s = 0.19, n = 23 For the part to fit properly in the assembled product, the
measurement should be 9.361. A) Normal distribution B) t distribution C) Neither Compute
the value of an appropriate test statistic for the given hypothesis test.
B) t distribution
You wish to test the claim that µ < 3.35 at the a = 0.02 significance level. In a sample of n =
25, the sample mean is 3.25 and the standard deviation is 0.87. Compute the value of the
appropriate test statistic. A) t = -0.11 B) t = -0.57 C) t = -2.87 D) t = 0.57
B) t = -0.57
State the critical value(s) and test the given claim using the traditional method. A large
software company gives job applicants a test of programming ability and the mean for that
test has been 160 in the past. Twenty-five job applicants are randomly selected from one
large university and they produce a mean score and standard deviation of 183 and 12,
respectively. Use a 0.05 level of significance to test the claim that this sample comes from a
population with a mean score greater than 160. A) The critical value is 1.711. There is
sufficient evidence to conclude that the mean is greater than 160. B) The critical value is
1.711. There is not sufficient evidence to conclude that the mean is greater than 160. C) The
critical values are +/- 2.064. There is sufficient evidence to conclude that the mean is greater
than 160. D) The critical values are +/- 2.064. There is not sufficient evidence to conclude
that the mean is greater than 160.
A) The critical value is 1.711. There is sufficient evidence to conclude that the mean is
greater than 160.
Assume that a hypothesis test of the given claim will be conducted. Identify the type I or type
II error for the test. A researcher claims that the amounts of acetaminophen in a certain brand
of cold tablets have a standard deviation different from the 3.3 mg claimed by the
manufacturer. Identify the type II error for the test. A) The error of rejecting the claim that
the standard deviation is more than 3.3 mg when it really is more than 3.3 mg. B) The error of
rejecting the claim that the standard deviation is 3.3 mg when it really is 3.3 mg. C) The error
of failing to reject the claim that the standard deviation is 3.3 mg when it is actually different
from 3.3 mg.
A) The error of rejecting the claim that the standard deviation is more than 3.3 mg
when it really is more than 3.3 mg.
Identify the null hypothesis H0 and the alternative hypothesis H1. Use µ for a claim about a
mean. Carter Motor Company claims that its new sedan, the Libra, will average better than 21
miles per gallon in the city. Use µ, the true average mileage of the Libra. A) H0: µ = 21 H1:
µ > 21 B) H0: µ = 21 H1: µ = 21 C) H0: µ = 21 H1: µ < 21 D) H0: µ = 21 H1: µ = 21
A) H0: µ = 21 H1: µ > 21