ECN 221 Midterm 3 Practice Test | Questions and
Answers | 2025 Update | 100% Correct.
What type of error occurs if you fail to reject H0 when, in fact, it is
not true? - ANSWER >>>>>Type II
For a lower tail test, the p-value is the probability of obtaining a
value for the test statistic as - ANSWER >>>>>smaller as or smaller
than thats provided with the sample
The p-value is a probability that measures the support (or lack of
support) for - ANSWER >>>>>the null hypothesis
The calorie content is listed as 241 calories for a prepared meal.
Tawnya tests a sample of 30 meals finding a mean of 249.6 calories
with a standard deviation of 7.8 calories. Test to determine if the
company preparing the meals is packaging meals with a different
calorie content than stated on the label at a 1% (0.01) level of
significance using the critical value approach. - ANSWER >>>>>The
hypotheses are H0: 𝜇 = 241 calories and Ha: 𝜇 ≠ 241 calories. The
test statistic is t = 6.039. The critical values are ±2.756. The
conclusion is to reject H0. We conclude that the mean calorie
content in meals is significantly different than 241 calories.
The proportion of Nadya's sales on Etsy that were returned after
purchase in the second quarter of the year was 0.073. To determine
if the proportion of purchases returned in the third quarter has
changed, Nadya selected a random sample of 200 sales finding 19
of them were returned. Conduct the appropriate test of hypothesis
at 𝛼 = 0.1 using the critical value method. - ANSWER >>>>>The
hypotheses are H0: p = 0.073 and Ha: p ≠ 0.073. The test statistic is
, z = 1.20. The critical values are ±1.645. The conclusion is to not
reject H0. We cannot conclude that the proportion of third quarter
returns is significantly different from the 7.3% in the second
quarter.
A Type II error is committed when - ANSWER >>>>>a true
alternative hypothesis is mistakenly rejected
The error of rejecting a true null hypothesis is - ANSWER >>>>>a
Type 1 error
When the following hypotheses are being tested at a level of
significance of 𝛼,
H0: 𝜇 ≥ 500
Ha: 𝜇 < 500
the null hypothesis will be rejected if - ANSWER >>>>>p-value ≤ 𝛼.
In a two-tailed hypothesis test situation, the test statistic is
determined to be
t = −2.035.
The sample size is 34. What is the p-value for this test? - ANSWER
>>>>>0.05
In a lower tail hypothesis test situation, the p-value is determined
to be 0.2. If the sample size for this test is 56, what is the value of
the t statistic? - ANSWER >>>>>-0.848
Read the t statistic from the t distribution table and choose the
correct ANSWER . For a one-tailed test (lower tail) with 22 degrees
of freedom at
𝛼 = 0.05,
find the critical t value. - ANSWER >>>>>-1.717
The average manufacturing work week in a particular city was 40.7
hours last year. It is believed that a recession has led to a reduction
Answers | 2025 Update | 100% Correct.
What type of error occurs if you fail to reject H0 when, in fact, it is
not true? - ANSWER >>>>>Type II
For a lower tail test, the p-value is the probability of obtaining a
value for the test statistic as - ANSWER >>>>>smaller as or smaller
than thats provided with the sample
The p-value is a probability that measures the support (or lack of
support) for - ANSWER >>>>>the null hypothesis
The calorie content is listed as 241 calories for a prepared meal.
Tawnya tests a sample of 30 meals finding a mean of 249.6 calories
with a standard deviation of 7.8 calories. Test to determine if the
company preparing the meals is packaging meals with a different
calorie content than stated on the label at a 1% (0.01) level of
significance using the critical value approach. - ANSWER >>>>>The
hypotheses are H0: 𝜇 = 241 calories and Ha: 𝜇 ≠ 241 calories. The
test statistic is t = 6.039. The critical values are ±2.756. The
conclusion is to reject H0. We conclude that the mean calorie
content in meals is significantly different than 241 calories.
The proportion of Nadya's sales on Etsy that were returned after
purchase in the second quarter of the year was 0.073. To determine
if the proportion of purchases returned in the third quarter has
changed, Nadya selected a random sample of 200 sales finding 19
of them were returned. Conduct the appropriate test of hypothesis
at 𝛼 = 0.1 using the critical value method. - ANSWER >>>>>The
hypotheses are H0: p = 0.073 and Ha: p ≠ 0.073. The test statistic is
, z = 1.20. The critical values are ±1.645. The conclusion is to not
reject H0. We cannot conclude that the proportion of third quarter
returns is significantly different from the 7.3% in the second
quarter.
A Type II error is committed when - ANSWER >>>>>a true
alternative hypothesis is mistakenly rejected
The error of rejecting a true null hypothesis is - ANSWER >>>>>a
Type 1 error
When the following hypotheses are being tested at a level of
significance of 𝛼,
H0: 𝜇 ≥ 500
Ha: 𝜇 < 500
the null hypothesis will be rejected if - ANSWER >>>>>p-value ≤ 𝛼.
In a two-tailed hypothesis test situation, the test statistic is
determined to be
t = −2.035.
The sample size is 34. What is the p-value for this test? - ANSWER
>>>>>0.05
In a lower tail hypothesis test situation, the p-value is determined
to be 0.2. If the sample size for this test is 56, what is the value of
the t statistic? - ANSWER >>>>>-0.848
Read the t statistic from the t distribution table and choose the
correct ANSWER . For a one-tailed test (lower tail) with 22 degrees
of freedom at
𝛼 = 0.05,
find the critical t value. - ANSWER >>>>>-1.717
The average manufacturing work week in a particular city was 40.7
hours last year. It is believed that a recession has led to a reduction
