Question 1

A sample standard deviation is the best point estimate of the

Accepted Answer

A)  population range. 
B)  population skewness. 
C)  population mode. 
D)  population standard deviation. 
E)  population variance. 
A)  population range. 
B)  population skewness. 
C)  population mode. 
D)  population standard deviation. 
E)  population variance.

Question 2

College X is concerned about their employees making use of their email for non-business purposes.
A random sample of 400 e-mails discovered 80 messages that were not business related. The 99%
Conﬁdence interval for the population proportion is:

Accepted Answer

A)  0.167 to 0.233 
B)  0.161 to 0.239 
C)  0.148 to 0.252 
D)  0.186 to 0.254 
E)  0.179 to 0.261 
A)  0.167 to 0.233 
B)  0.161 to 0.239 
C)  0.148 to 0.252 
D)  0.186 to 0.254 
E)  0.179 to 0.261

Question 3

College X is concerned about their employees making use of their email for non-business purposes.
You have been approached to assist in this matter. College X decides on a 99% conﬁdence level
And state that the estimation proportion must be within 2 percent of the population proportion. A
Pilot survey reveals that 10 out of 50 emails sampled were not for business purposes. How many
Emails should be surveyed to meet your requirements?

Accepted Answer

A)  910 
B)  1,537 
C)  1,083 
D)  1,221 
E)  2,663 
A)  910 
B)  1,537 
C)  1,083 
D)  1,221 
E)  2,663

Question 4

i. The t distribution is based on the assumption that the population of interest is normal or nearly
Normal.
ii. The t distribution is a continuous distribution.
iii. There is not one t distribution, but rather a "family" of t distributions.

Accepted Answer

A)  (i), (ii), and (iii) are all correct statements. 
B)  (i) is a correct statement but not (ii) or (iii). 
C)  (i) and (iii) are correct statements but not (ii). 
D)  (ii) and (iii) are correct statements but not (i). 
E)  (i), (ii), and (iii) are all false statements. 
A)  (i), (ii), and (iii) are all correct statements. 
B)  (i) is a correct statement but not (ii) or (iii). 
C)  (i) and (iii) are correct statements but not (ii). 
D)  (ii) and (iii) are correct statements but not (i). 
E)  (i), (ii), and (iii) are all false statements.

Question 5

What kind of distribution is the t distribution?

Accepted Answer

A)  Continuous 
B)  Discrete 
C)  Subjective 
D)  Standard 
A)  Continuous 
B)  Discrete 
C)  Subjective 
D)  Standard

Question 6

The sample size needed to estimate a population mean within 2 units with a 95% conﬁdence when
The population standard deviation equals 8 is

Accepted Answer

A)  9 
B)  61 
C)  62 
D)  8 
E)  50 
A)  9 
B)  61 
C)  62 
D)  8 
E)  50

Question 7

The z-value associated with a 90% level of conﬁdence is:

Accepted Answer

A)  1.96 
B)  1.645 
C)  2.33 
D)  2.575 
E)  1.28 
A)  1.96 
B)  1.645 
C)  2.33 
D)  2.575 
E)  1.28

Question 8

The Sugar Producers Association wants to estimate the mean yearly sugar consumption. A sample
Of 25 people reveals the mean yearly consumption to be 27 kg with a sample standard deviation of
9 kg. Assume a normal population. Develop a 99% conﬁdence interval for the mean annual
Consumption of sugar.

Accepted Answer

A)  23.06 to 30.94 
B)  23.285 to 30.715 
C)  21.97 to 32.03 
D)  23.30 to 30.70 
E)  23.92 to 30.08 
A)  23.06 to 30.94 
B)  23.285 to 30.715 
C)  21.97 to 32.03 
D)  23.30 to 30.70 
E)  23.92 to 30.08

Question 9

The z-value associated with a 94% level of conﬁdence is:

Accepted Answer

A)  1.96 
B)  1.645 
C)  2.33 
D)  2.575 
E)  1.88 
A)  1.96 
B)  1.645 
C)  2.33 
D)  2.575 
E)  1.88

Question 10

A sample mean is the best point estimate of the

Accepted Answer

A)  population standard deviation. 
B)  population median. 
C)  population mean. 
D)  the sample standard deviation. 
E)  the population variance. 
A)  population standard deviation. 
B)  population median. 
C)  population mean. 
D)  the sample standard deviation. 
E)  the population variance.

Question 11

i. The t distribution is positively skewed.
ii. All t distributions have the same mean of zero and a standard deviation of 1.
iii. The t distribution is more spread out and ﬂatter at the center than is the standard normal
Distribution. However, as the sample size increases, the t distribution curve approaches the
Standard normal distribution.

Accepted Answer

A)  (i), (ii), and (iii) are all correct statements. 
B)  (iii) is a correct statement but not (i) or (ii). 
C)  (i) and (iii) are correct statements but not (ii). 
D)  (ii) and (iii) are correct statements but not (i). 
E)  (i), (ii), and (iii) are all false statements. 
A)  (i), (ii), and (iii) are all correct statements. 
B)  (iii) is a correct statement but not (i) or (ii). 
C)  (i) and (iii) are correct statements but not (ii). 
D)  (ii) and (iii) are correct statements but not (i). 
E)  (i), (ii), and (iii) are all false statements.

Question 12

The t distribution approaches __________ as the sample size increases.
As the sample size increases, the computed value of t ______________.

Accepted Answer

A)  Z distribution; decreases 
B)  Z distribution; increases 
C)  Z distribution; stays the same 
D)  0; decreases 
E)  0; increases 
A)  Z distribution; decreases 
B)  Z distribution; increases 
C)  Z distribution; stays the same 
D)  0; decreases 
E)  0; increases

Question 13

A student wanted to quickly construct a 99% conﬁdence interval for the average age of students in
Her statistics class. She randomly selected 9 students. Their average age was 19.1 years with a
Standard deviation of 1.5 years. What is the 99% conﬁdence interval for the population mean?

Accepted Answer

A)  [17.42, 20.78] 
B)  [17.48, 20.72] 
C)  [14.23, 23.98] 
D)  [0.44, 3.80] 
E)  [17.95, 20.25] 
A)  [17.42, 20.78] 
B)  [17.48, 20.72] 
C)  [14.23, 23.98] 
D)  [0.44, 3.80] 
E)  [17.95, 20.25]

Question 14

A sample of 500 executives who own their own home revealed 175 planned to sell their homes and
Retire to Victoria. Develop a 98% conﬁdence interval for the proportion of executives that plan to
Sell and move to Victoria.

Accepted Answer

A)  30% and 40% 
B)  29% and 41% 
C)  28% and 42% 
D)  29.5% and 40.5% 
E)  29.3% and 41.3% 
A)  30% and 40% 
B)  29% and 41% 
C)  28% and 42% 
D)  29.5% and 40.5% 
E)  29.3% and 41.3%

A sample standard deviation is the best point estimate of the

College X is concerned about their employees making use of their email for non-business purposes. A random sample of 400 e-mails discovered 80 messages that were not business related. The 99% Conﬁdence interval for the population proportion is:

i. The t distribution is based on the assumption that the population of interest is normal or nearly Normal. ii. The t distribution is a continuous distribution. iii. There is not one t distribution, but rather a "family" of t distributions.

What kind of distribution is the t distribution?

The sample size needed to estimate a population mean within 2 units with a 95% conﬁdence when The population standard deviation equals 8 is

The z-value associated with a 90% level of conﬁdence is:

The z-value associated with a 94% level of conﬁdence is:

A sample mean is the best point estimate of the

The t distribution approaches as the sample size increases. As the sample size increases, the computed value of t ____.

A student wanted to quickly construct a 99% conﬁdence interval for the average age of students in Her statistics class. She randomly selected 9 students. Their average age was 19.1 years with a Standard deviation of 1.5 years. What is the 99% conﬁdence interval for the population mean?

A sample of 500 executives who own their own home revealed 175 planned to sell their homes and Retire to Victoria. Develop a 98% conﬁdence interval for the proportion of executives that plan to Sell and move to Victoria.

What Is Statistics

Describing Data: Frequencydistributions and Graphic Presentation

Describing Data: Numerical Measures

Describing Data: Displaying and Exploring Pata

A Sulvey of Probability Concepts

Discrete Probability Distributions

Continuous Probabilitydistributions

Estimation and Confidence Intervals

One-Sample Tests of Hypothesis

Two Sample Tests of Hypothesis

Analysis of Variance

Linear Regression and Correlation

Multiple Regression and Correlation Analysis

Chi-Square Applications

Decision Making and Payoff Tables in Investment Scenarios

Filters

Exam 8: Sampling Methods and the Central Umit Theorem

A sample standard deviation is the best point estimate of the

College X is concerned about their employees making use of their email for non-business purposes. A random sample of 400 e-mails discovered 80 messages that were not business related. The 99% Conﬁdence interval for the population proportion is:

i. The t distribution is based on the assumption that the population of interest is normal or nearly Normal. ii. The t distribution is a continuous distribution. iii. There is not one t distribution, but rather a "family" of t distributions.

What kind of distribution is the t distribution?

The sample size needed to estimate a population mean within 2 units with a 95% conﬁdence when The population standard deviation equals 8 is

The z-value associated with a 90% level of conﬁdence is:

The z-value associated with a 94% level of conﬁdence is:

A sample mean is the best point estimate of the

The t distribution approaches __________ as the sample size increases. As the sample size increases, the computed value of t ______________.

A student wanted to quickly construct a 99% conﬁdence interval for the average age of students in Her statistics class. She randomly selected 9 students. Their average age was 19.1 years with a Standard deviation of 1.5 years. What is the 99% conﬁdence interval for the population mean?

A sample of 500 executives who own their own home revealed 175 planned to sell their homes and Retire to Victoria. Develop a 98% conﬁdence interval for the proportion of executives that plan to Sell and move to Victoria.

What Is Statistics

Describing Data: Frequencydistributions and Graphic Presentation

Describing Data: Numerical Measures

Describing Data: Displaying and Exploring Pata

A Sulvey of Probability Concepts

Discrete Probability Distributions

Continuous Probabilitydistributions

Estimation and Confidence Intervals

One-Sample Tests of Hypothesis

Two Sample Tests of Hypothesis

Analysis of Variance

Linear Regression and Correlation

Multiple Regression and Correlation Analysis

Chi-Square Applications

Decision Making and Payoff Tables in Investment Scenarios

Filters

The t distribution approaches as the sample size increases. As the sample size increases, the computed value of t ____.