Question 1

If α = 0.05, what is the probability of making a Type I error?

Accepted Answer

1/20

Question 2

i. The probability of a Type I error is also referred to as alpha.
ii. A Type I error is the probability of accepting a true null hypothesis.
iii. A Type I error is the probability of rejecting a true null hypothesis.

Accepted Answer

(i) is a correct statement but (ii) or (iii).

Question 3

It is claimed that in a bushel of peaches less than ten percent are defective. A sample of 400
Peaches is examined and 50 are found to be defective. What is the critical value for α = 0.025?

Accepted Answer

-1.96

Question 4

Based on the Nielsen ratings, the local CBS aﬃliate claims its 11:00 PM newscast reaches 41% of the
Viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late
Evening news on this local CBS station.
What is your decision if α = 0.01?

Accepted Answer

Fail to reject the null hypothesis and conclude about 41%.

Question 5

A manufacturer claims that less than 1% of all his products do not meet the minimum government
Standards. A survey of 500 products revealed ten did not meet the standard.

Accepted Answer

If α = .01, the critical value is z = -2.33

Question 6

The mean gross annual incomes of certiﬁed tack welders are normally distributed with the mean of
$50,000 and a standard deviation of $4,000. The ship building association wishes to ﬁnd out
Whether their tack welders earn more or less than $50,000 annually. The alternate hypothesis is
That the mean is not $50,000.
Given the following megastat printout, what conclusions can be made?

Accepted Answer

Since the p-value is incredibly small (far less than 1%), we reject the null hypothesis at the

Question 7

What is the probability of making a Type II error if the null hypothesis is actually true?

Accepted Answer

0

Question 8

Based on the Nielsen ratings, the local CBS aﬃliate claims its 11:00 PM newscast reaches 41% of the
Viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late
Evening news on this local CBS station.
What is the critical value if the level of signiﬁcance is 0.10?

Accepted Answer

±1.65

Question 9

Based on the Nielsen ratings, the local CBS aﬃliate claims its 11:00 PM newscast reaches 41% of the
Viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late
Evening news on this local CBS station.
What is the z-statistic?

Accepted Answer

-1.02

Question 10

A manufacturer claims that less than 1% of all his products do not meet the minimum government
Standards. A survey of 500 products revealed ten did not meet the standard.
If the level of signiﬁcance is 2%, what is the critical value?

Accepted Answer

-2.05

Question 11

What is the level of signiﬁcance?

Accepted Answer

Probability of a Type I error

Question 12

i. If the critical values of the test statistic z are ±1.96, they are the dividing points between the areas
Of rejection and non-rejection.
ii. The probability of a Type I error is also referred to as alpha.
iii. A Type I error is the probability of rejecting a true null hypothesis.

Accepted Answer

(i), (ii), and (iii) are all correct statements.

Question 13

A manufacturer claims that less than 1% of all his products do not meet the minimum government
Standards. A survey of 500 products revealed ten did not meet the standard.

Accepted Answer

The z-statistic is 2.25

Question 14

It is claimed that in a bushel of peaches less than ten percent are defective. A sample of 400
Peaches is examined and 50 are found to be defective. What is the null hypothesis?

Accepted Answer

p ≥ 0.10

Question 15

What is a Type II error?

Accepted Answer

Accepting a false null hypothesis

Question 16

A manufacturer claims that less than 1% of all his products do not meet the minimum government
Standards. A survey of 500 products revealed ten did not meet the standard.
If the z-statistic is -1.96 and the level of signiﬁcance is 0.01, what is your decision?

Accepted Answer

You have insuﬃcient evidence to reject the null hypothesis.

Question 17

It is claimed that in a bushel of peaches less than ten percent are defective. A sample of 400
Peaches is examined and 50 are found to be defective. What is the z-statistic?

Accepted Answer

1.67

Question 18

It is claimed that in a bushel of peaches less than ten percent are defective. A sample of 400
Peaches is examined and 50 are found to be defective. What is the sample proportion?

Accepted Answer

0.125

Question 19

i. If the critical values of the test statistic z are ±1.96, they are the dividing points between the areas
Of rejection and non-rejection.
ii. The probability of a Type I error is also referred to as alpha.
iii. A Type I error is the probability of accepting a true null hypothesis.

Accepted Answer

(i) and (ii) are correct statements but (iii).

Question 20

A manufacturer claims that less than 1% of all his products do not meet the minimum government
Standards. A survey of 500 products revealed ten did not meet the standard.

Accepted Answer

The null hypothesis is p ≥ 0.01. The alternate hypothesis is p < 0.01

Quiz 9: Estimation and Confidence Intervals

If α = 0.05, what is the probability of making a Type I error?

i. The probability of a Type I error is also referred to as alpha. ii. A Type I error is the probability of accepting a true null hypothesis. iii. A Type I error is the probability of rejecting a true null hypothesis.

It is claimed that in a bushel of peaches less than ten percent are defective. A sample of 400 Peaches is examined and 50 are found to be defective. What is the critical value for α = 0.025?

Based on the Nielsen ratings, the local CBS aﬃliate claims its 11:00 PM newscast reaches 41% of the Viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late Evening news on this local CBS station. What is your decision if α = 0.01?

A manufacturer claims that less than 1% of all his products do not meet the minimum government Standards. A survey of 500 products revealed ten did not meet the standard.

What is the probability of making a Type II error if the null hypothesis is actually true?

Based on the Nielsen ratings, the local CBS aﬃliate claims its 11:00 PM newscast reaches 41% of the Viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late Evening news on this local CBS station. What is the z-statistic?

A manufacturer claims that less than 1% of all his products do not meet the minimum government Standards. A survey of 500 products revealed ten did not meet the standard. If the level of signiﬁcance is 2%, what is the critical value?

What is the level of signiﬁcance?

i. If the critical values of the test statistic z are ±1.96, they are the dividing points between the areas Of rejection and non-rejection. ii. The probability of a Type I error is also referred to as alpha. iii. A Type I error is the probability of rejecting a true null hypothesis.

A manufacturer claims that less than 1% of all his products do not meet the minimum government Standards. A survey of 500 products revealed ten did not meet the standard.

It is claimed that in a bushel of peaches less than ten percent are defective. A sample of 400 Peaches is examined and 50 are found to be defective. What is the null hypothesis?

What is a Type II error?

A manufacturer claims that less than 1% of all his products do not meet the minimum government Standards. A survey of 500 products revealed ten did not meet the standard. If the z-statistic is -1.96 and the level of signiﬁcance is 0.01, what is your decision?

It is claimed that in a bushel of peaches less than ten percent are defective. A sample of 400 Peaches is examined and 50 are found to be defective. What is the z-statistic?

It is claimed that in a bushel of peaches less than ten percent are defective. A sample of 400 Peaches is examined and 50 are found to be defective. What is the sample proportion?

i. If the critical values of the test statistic z are ±1.96, they are the dividing points between the areas Of rejection and non-rejection. ii. The probability of a Type I error is also referred to as alpha. iii. A Type I error is the probability of accepting a true null hypothesis.

A manufacturer claims that less than 1% of all his products do not meet the minimum government Standards. A survey of 500 products revealed ten did not meet the standard.