QMB 3200 MIDTERM UCF EXAM QUESTIONS AND
CORRECT ANSWERS| ACCURATE REAL EXAM WITH
FREQUENTLY TESTED QUESTIONS AND
RATIONALE|ALREADY A GRADED|GUARANTEED
PASS|LATEST UPDATE 2025.
When computing the sample size needed to estimate a proportion within a given margin of error
for a specific confidence level, what planning value of p should be used when no estimate of p is
available? - CORRECT ANSWER 0.50
A statistics teacher started class one day by drawing the names of 10 students out of a hat and
asked them to do as many pushups as they could. The 10 randomly selected students averaged 15
pushups per person with a standard deviation of 9 pushups. Suppose the distribution of the
population of number of pushups that can be done is approximately normal. Which of the
following statements is true? - CORRECT ANSWER A t distribution should be used because σ
is unknown.
The z value for a 99% confidence interval estimation is - CORRECT ANSWER 2.58
In an interval estimation for a proportion of a population, the critical value of z at 99%
confidence is - CORRECT ANSWER 2.576.
In interval estimation, as the sample size becomes larger, the interval estimate - CORRECT
ANSWER becomes narrower.In general, higher confidence levels provide larger confidence
intervals.
One way to have high confidence and a small margin of error is to - CORRECT ANSWER
increase the sample size.
From a population that is normally distributed, a sample of 30 elements is selected and the
standard deviation of the sample is computed. For the interval estimation of μ, the proper
distribution to use is the - CORRECT ANSWER t distribution with 29 degrees of freedom.
As the number of degrees of freedom for a t distribution increases, the difference between the t
distribution and the standard normal distribution - CORRECT ANSWER becomes smaller.
The value added and subtracted from a point estimate in order to develop an interval estimate of
the population parameter is known as the - CORRECT ANSWER margin of error.
What is the symbol for the population mean? If the population follows a normal distribution, the
confidence interval is _____ and can be used for any sample size. If the population does not
follow a normal distribution, the confidence interval will be _____. Which of the following
choices correctly complete this statement? - CORRECT ANSWER exact; approximate.
,The t value for a 99% confidence interval estimation based upon a sample of size 10 is -
CORRECT ANSWER 3.250.
To compute the necessary sample size for an interval estimate of a population proportion, all of
the following procedures are recommended when p is unknown except - CORRECT ANSWER
using .95 as an estimate.
Using an α = .04, a confidence interval for a population proportion is determined to be .65 to .75.
If the level of significance is decreased, the interval for the population proportion - CORRECT
ANSWER becomes wider.
For a fixed confidence level and population standard deviation, if we would like to cut our
margin of error to 1/3 of the original size, we should take a sample size that is - CORRECT
ANSWER nine times as large as the original sample size.
The sampling distribution of can be approximated by a normal distribution as long as -
CORRECT ANSWER np> 5 and n(1-p)>5 greater or equals.
When "s" is used to estimate "σ," the margin of error is computed by using the - CORRECT
ANSWER t distribution.
The margin of error in an interval estimate of the population mean is a function of all of the
following except the - CORRECT ANSWER sample mean.
For a fixed sample size, n, in order to have a higher degree of confidence, the margin of error and
the width of the interval - CORRECT ANSWER must be larger.
The probability that the interval estimation procedure will generate an interval that does not
contain µ is known as the - CORRECT ANSWER level of significance.
As the sample size increases, the margin of error - CORRECT ANSWER decreases.
When the level of confidence decreases, the margin of error - CORRECT ANSWER becomes
smaller.
An approximate value of a population parameter that provides limits and believed to contain the
value of the parameter is known as - CORRECT ANSWER the interval estimate.
To compute the necessary sample size for an interval estimate of a population mean, all of the
following procedures are recommended when σ is unknown except - CORRECT ANSWER
using σ = 1.
For the interval estimation of μ when σ is known and the sample is large, the proper distribution
to use is - CORRECT ANSWER the normal distribution.
What is the symbol for the sample mean? - CORRECT ANSWER X bar
,A student wants to determine if pennies are really fair, meaning equally likely to land heads up
or tails up. He flips a random sample of 50 pennies and finds that 28 of them land heads up.
What are the appropriate null and alternative hypotheses? - CORRECT ANSWER H0: p=.5,
Ha:p not =.5.
For a lower tail test, the p-value is the probability of obtaining a value for the test statistic -
CORRECT ANSWER at least as small as that provided by the sample.
The average hourly wage of computer programmers with 2 years of experience has been $21.80.
Because of high demand for computer programmers, it is believed there has been a significant
increase in the average wage of computer programmers. To test whether there has been an
increase, the correct hypotheses to be tested are - CORRECT ANSWER H0:u<21.80, Ha:
u>21.80.
In hypothesis testing, the tentative assumption about the population parameter is called -
CORRECT ANSWER the null hypothesis.
For a two-tailed test, the p-value is the probability of obtaining a value for the test statistic as -
CORRECT ANSWER unlikely as that provided by the sample.
The average number of hours for a random sample of mail order pharmacists from company A
was 50.1 hours last year. It is believed that changes to medical insurance have led to a reduction
in the average work week. To test the validity of this belief, the hypotheses are - CORRECT
ANSWER H0:u>50.1, Ha:u<50.1.
Whenever the probability of making a Type II error has not been determined and controlled, only
two conclusions are possible. We either reject H0 or - CORRECT ANSWER Do not reject H0.
Applications of hypothesis testing that only control for the Type I error are called - CORRECT
ANSWER significance tests.
The p-value is a probability that measures the support (or lack of support) for the - CORRECT
ANSWER null hypothesis.
As the test statistic becomes larger, the p-value - CORRECT ANSWER becomes smaller.
A news reporter states that the average number of temperature in January has never dropped
below 10 degrees Fahrenheit. You go online to research this claim. The appropriate hypotheses
are - CORRECT ANSWER H0: u>10, Ha: u<10.
The probability of making a Type I error when the null hypothesis is true as an equality is called
the - CORRECT ANSWER level of significance.
Which of the following null hypotheses cannot be correct? - CORRECT ANSWER H0: u
not=10.
, It has been stated that at least 75 out of every 100 people who go to the movies on Saturday night
buy popcorn. Identify the null and alternative hypotheses. - CORRECT ANSWER H0: p>.75,
Ha: p<.75.
A fast food restaurant has automatic drink dispensers to help fill orders more quickly. When the
12 ounce button is pressed, they would like for exactly 12 ounces of beverage to be dispensed.
There is, however, undoubtedly some variation in this amount. The company does not want the
machine to systematically over fill or under fill the cups. Which of the following gives the
correct set of hypotheses? - CORRECT ANSWER H0: u=12, Ha: u not=12
Which of the following describes a Type II Error? - CORRECT ANSWER Accept H0 when H0
is false.
Which of the following does not need to be known in order to compute the p-value? -
CORRECT ANSWER The level of significance.
What is the probability of making a Type I error? - CORRECT ANSWER 𝛼 alpha.
The p-value - CORRECT ANSWER must be a number between 0 and 1.
The normal probability distribution can be used to approximate the sampling distribution of as
long as - CORRECT ANSWER np>5 and n(1-p)>5.
For the case where σ is unknown, which statistic is used to estimate σ? - CORRECT ANSWER
S
For the case where σ is unknown, the test statistic has a t distribution. How many degrees of
freedom does it have? n-1Which of the following describes a Type I Error? - CORRECT
ANSWER Reject H0 when H0 is true.
The matched sample design often leads to a smaller sampling error than the independent sample
design. The primary reason is that in a matched sample design - CORRECT ANSWER variation
between subjects is eliminated because the same subjects are used for both treatments.
Suppose we are constructing an interval estimate for the difference between the means of two
populations when the standard deviations of the two populations are unknown. Suppose it can be
assumed that the two populations have equal variances. If n1 is the size of sample 1 and n2 is the
size of sample 2, we must use a t distribution with - CORRECT ANSWER degrees of freedom.
A researcher recruits 25 people to participate in a study on alcohol consumption and its
interactions with Tylenol. The 25 participants had to come to a check-in center every day at 7:00
a.m. for one week. They were given various amounts of alcohol. Each day, each participant
would flip a coin to determine if they also took Tylenol with their alcohol. They found that their
BAC was 25% higher on days when they were given Tylenol with their alcohol than when they
drank alcohol alone. This is an example of a(n) - CORRECT ANSWER matched sample design.
CORRECT ANSWERS| ACCURATE REAL EXAM WITH
FREQUENTLY TESTED QUESTIONS AND
RATIONALE|ALREADY A GRADED|GUARANTEED
PASS|LATEST UPDATE 2025.
When computing the sample size needed to estimate a proportion within a given margin of error
for a specific confidence level, what planning value of p should be used when no estimate of p is
available? - CORRECT ANSWER 0.50
A statistics teacher started class one day by drawing the names of 10 students out of a hat and
asked them to do as many pushups as they could. The 10 randomly selected students averaged 15
pushups per person with a standard deviation of 9 pushups. Suppose the distribution of the
population of number of pushups that can be done is approximately normal. Which of the
following statements is true? - CORRECT ANSWER A t distribution should be used because σ
is unknown.
The z value for a 99% confidence interval estimation is - CORRECT ANSWER 2.58
In an interval estimation for a proportion of a population, the critical value of z at 99%
confidence is - CORRECT ANSWER 2.576.
In interval estimation, as the sample size becomes larger, the interval estimate - CORRECT
ANSWER becomes narrower.In general, higher confidence levels provide larger confidence
intervals.
One way to have high confidence and a small margin of error is to - CORRECT ANSWER
increase the sample size.
From a population that is normally distributed, a sample of 30 elements is selected and the
standard deviation of the sample is computed. For the interval estimation of μ, the proper
distribution to use is the - CORRECT ANSWER t distribution with 29 degrees of freedom.
As the number of degrees of freedom for a t distribution increases, the difference between the t
distribution and the standard normal distribution - CORRECT ANSWER becomes smaller.
The value added and subtracted from a point estimate in order to develop an interval estimate of
the population parameter is known as the - CORRECT ANSWER margin of error.
What is the symbol for the population mean? If the population follows a normal distribution, the
confidence interval is _____ and can be used for any sample size. If the population does not
follow a normal distribution, the confidence interval will be _____. Which of the following
choices correctly complete this statement? - CORRECT ANSWER exact; approximate.
,The t value for a 99% confidence interval estimation based upon a sample of size 10 is -
CORRECT ANSWER 3.250.
To compute the necessary sample size for an interval estimate of a population proportion, all of
the following procedures are recommended when p is unknown except - CORRECT ANSWER
using .95 as an estimate.
Using an α = .04, a confidence interval for a population proportion is determined to be .65 to .75.
If the level of significance is decreased, the interval for the population proportion - CORRECT
ANSWER becomes wider.
For a fixed confidence level and population standard deviation, if we would like to cut our
margin of error to 1/3 of the original size, we should take a sample size that is - CORRECT
ANSWER nine times as large as the original sample size.
The sampling distribution of can be approximated by a normal distribution as long as -
CORRECT ANSWER np> 5 and n(1-p)>5 greater or equals.
When "s" is used to estimate "σ," the margin of error is computed by using the - CORRECT
ANSWER t distribution.
The margin of error in an interval estimate of the population mean is a function of all of the
following except the - CORRECT ANSWER sample mean.
For a fixed sample size, n, in order to have a higher degree of confidence, the margin of error and
the width of the interval - CORRECT ANSWER must be larger.
The probability that the interval estimation procedure will generate an interval that does not
contain µ is known as the - CORRECT ANSWER level of significance.
As the sample size increases, the margin of error - CORRECT ANSWER decreases.
When the level of confidence decreases, the margin of error - CORRECT ANSWER becomes
smaller.
An approximate value of a population parameter that provides limits and believed to contain the
value of the parameter is known as - CORRECT ANSWER the interval estimate.
To compute the necessary sample size for an interval estimate of a population mean, all of the
following procedures are recommended when σ is unknown except - CORRECT ANSWER
using σ = 1.
For the interval estimation of μ when σ is known and the sample is large, the proper distribution
to use is - CORRECT ANSWER the normal distribution.
What is the symbol for the sample mean? - CORRECT ANSWER X bar
,A student wants to determine if pennies are really fair, meaning equally likely to land heads up
or tails up. He flips a random sample of 50 pennies and finds that 28 of them land heads up.
What are the appropriate null and alternative hypotheses? - CORRECT ANSWER H0: p=.5,
Ha:p not =.5.
For a lower tail test, the p-value is the probability of obtaining a value for the test statistic -
CORRECT ANSWER at least as small as that provided by the sample.
The average hourly wage of computer programmers with 2 years of experience has been $21.80.
Because of high demand for computer programmers, it is believed there has been a significant
increase in the average wage of computer programmers. To test whether there has been an
increase, the correct hypotheses to be tested are - CORRECT ANSWER H0:u<21.80, Ha:
u>21.80.
In hypothesis testing, the tentative assumption about the population parameter is called -
CORRECT ANSWER the null hypothesis.
For a two-tailed test, the p-value is the probability of obtaining a value for the test statistic as -
CORRECT ANSWER unlikely as that provided by the sample.
The average number of hours for a random sample of mail order pharmacists from company A
was 50.1 hours last year. It is believed that changes to medical insurance have led to a reduction
in the average work week. To test the validity of this belief, the hypotheses are - CORRECT
ANSWER H0:u>50.1, Ha:u<50.1.
Whenever the probability of making a Type II error has not been determined and controlled, only
two conclusions are possible. We either reject H0 or - CORRECT ANSWER Do not reject H0.
Applications of hypothesis testing that only control for the Type I error are called - CORRECT
ANSWER significance tests.
The p-value is a probability that measures the support (or lack of support) for the - CORRECT
ANSWER null hypothesis.
As the test statistic becomes larger, the p-value - CORRECT ANSWER becomes smaller.
A news reporter states that the average number of temperature in January has never dropped
below 10 degrees Fahrenheit. You go online to research this claim. The appropriate hypotheses
are - CORRECT ANSWER H0: u>10, Ha: u<10.
The probability of making a Type I error when the null hypothesis is true as an equality is called
the - CORRECT ANSWER level of significance.
Which of the following null hypotheses cannot be correct? - CORRECT ANSWER H0: u
not=10.
, It has been stated that at least 75 out of every 100 people who go to the movies on Saturday night
buy popcorn. Identify the null and alternative hypotheses. - CORRECT ANSWER H0: p>.75,
Ha: p<.75.
A fast food restaurant has automatic drink dispensers to help fill orders more quickly. When the
12 ounce button is pressed, they would like for exactly 12 ounces of beverage to be dispensed.
There is, however, undoubtedly some variation in this amount. The company does not want the
machine to systematically over fill or under fill the cups. Which of the following gives the
correct set of hypotheses? - CORRECT ANSWER H0: u=12, Ha: u not=12
Which of the following describes a Type II Error? - CORRECT ANSWER Accept H0 when H0
is false.
Which of the following does not need to be known in order to compute the p-value? -
CORRECT ANSWER The level of significance.
What is the probability of making a Type I error? - CORRECT ANSWER 𝛼 alpha.
The p-value - CORRECT ANSWER must be a number between 0 and 1.
The normal probability distribution can be used to approximate the sampling distribution of as
long as - CORRECT ANSWER np>5 and n(1-p)>5.
For the case where σ is unknown, which statistic is used to estimate σ? - CORRECT ANSWER
S
For the case where σ is unknown, the test statistic has a t distribution. How many degrees of
freedom does it have? n-1Which of the following describes a Type I Error? - CORRECT
ANSWER Reject H0 when H0 is true.
The matched sample design often leads to a smaller sampling error than the independent sample
design. The primary reason is that in a matched sample design - CORRECT ANSWER variation
between subjects is eliminated because the same subjects are used for both treatments.
Suppose we are constructing an interval estimate for the difference between the means of two
populations when the standard deviations of the two populations are unknown. Suppose it can be
assumed that the two populations have equal variances. If n1 is the size of sample 1 and n2 is the
size of sample 2, we must use a t distribution with - CORRECT ANSWER degrees of freedom.
A researcher recruits 25 people to participate in a study on alcohol consumption and its
interactions with Tylenol. The 25 participants had to come to a check-in center every day at 7:00
a.m. for one week. They were given various amounts of alcohol. Each day, each participant
would flip a coin to determine if they also took Tylenol with their alcohol. They found that their
BAC was 25% higher on days when they were given Tylenol with their alcohol than when they
drank alcohol alone. This is an example of a(n) - CORRECT ANSWER matched sample design.
