QMB 3200 UCF MIDTERM EXAM COMPLETE ACTUAL
EXAM QUESTIONS AND CORRECT VERIFIED ANSWERS
(FULL REVISED EXAM) LATEST UPDATED VERSION |
ALREADY GRADED A+
In computing the standard error of the mean, the finite population correction factor
is not used when:
a. n ≥ 30
b. n/N ≤ 0.05
c. N/n ≤ 0.05
d. n/N > 0.05 - ANSWER: b. n/N ≤ 0.05
A sample statistic, such as x bar , that estimates the value of the corresponding
population parameter is known as a:
a. population parameter
b. point estimator
c. Both a parameter and a population parameter are correct.
d. parameter - ANSWER: b. point estimator
The standard deviation of xbar is referred to as the
a. standard error of the mean
b. standard x
c. sample standard mean
d. sample mean deviation - ANSWER: a. standard error of the mean
Which of the following is(are) point estimator(s)?
a. σ
b. μ
c. s
d. All of these answers are correct. - ANSWER: c. s
A probability distribution for all possible values of a sample statistic is known as a
a. parameter
b. sample statistic
c. sampling distribution
d. simple random sample - ANSWER: c. sampling distribution
A population has a mean of 180 and a standard deviation of 24. A sample of 64
observations will be taken. The probability that the mean from that sample will be
between 183 and 186 is
a. 0.8185
b. 0.1359
c. 0.4772
d. 0.3413 - ANSWER: b. 0.1359
,1. st. error: 24/sqrt(64) = 3
2. z value (upper): (186-180)/3 = 2
3. Norm.s.dist(1, true) = .9772
4. z value (lower): (183-180)/3= 1
5.Norm.s.dist(-1,true)= .8413
6. 0.9772-.8413=0.1359
The basis for using a normal probability distribution to approximate the sampling
distribution of xbar and pbar is:
a. the empirical rule
b. the central limit theorem
c. Chebyshev's theorem
d. Bayes' theorem - ANSWER: b. the central limit theorem
A finite population correction factor is needed in computing the standard deviation
of the sampling distribution of sample means:
a. whenever the sample size is less than 5% of the population size
b. whenever the population is infinite
c. whenever the sample size is more than 5% of the population size
d. The correction factor is not necessary if the population has a normal distribution -
ANSWER: c. whenever the sample size is more than 5% of the population size
A sample of 66 observations will be taken from a process (an infinite population).
The population proportion equals 0.12. The probability that the sample proportion
will be less than 0.1768 is
a. 0.4222
b. 0.0778
c. 0.9222
d. 0.0568 - ANSWER: c. 0.9222
1. Mean of the sample proportions = 0.12
2. St. dev. of pbar = sqrt [ p(1-p) / n] = sqrt [ (0.12)(1-.12) / 66] = .04
μ = 0.12
σ = 0.04
3. standardize x to z = (x - μ) / σ = (0.1768-0.12) / 0.04 = 1.42
4. norm.s.dist(1.42,true) = 0.9222
A population has a mean of 53 and a standard deviation of 21. A sample of 49
observations will be taken. The probability that the sample mean will be greater than
57.95 is
a. 0
b. .0495
c. .4505
d. None of the alternative answers is correct. - ANSWER: b. .0495
1. 21/sqrt(49)=3
2. 57.93-53=4.95
, 3. 4.95/3 = 1.65
4.norm.s.dist(1.65,true) = .9505
5. 1-.9505= .0495
A numerical measure from a sample, such as a sample mean, is known as
a. a parameter
b. a statistic
c. the central limit theorem
d. the mean deviation - ANSWER: b. a statistic
T/F
Sampling is used to make an inference or answer a research question about a
population - ANSWER: True
T/F
In a simple random sample, when sampling a infinite population, you can use the
RAND excel function. - ANSWER: False
The population that you want to make inferences about when sampling is the
a. Sample population
b. Inferenced sample
c. Target population
d. Judgmental sample - ANSWER: c. Target population
A numerical characteristic of a population, such as the population mean, is known as:
a. sample characteristic
b. sample statistic
c. simple sample
d. parameter - ANSWER: d. parameter
The sample statistic, such as the sample mean, or the sample standard deviation is
known as:
a. Standard error
b. Sample statistic
c. point estimator
d. target estimator - ANSWER: c. point estimator
The standard deviation of a point estimator is:
a. Standard error
b. Sample error
c. Population error
d. Unbiased error - ANSWER: a. Standard error
EXAM QUESTIONS AND CORRECT VERIFIED ANSWERS
(FULL REVISED EXAM) LATEST UPDATED VERSION |
ALREADY GRADED A+
In computing the standard error of the mean, the finite population correction factor
is not used when:
a. n ≥ 30
b. n/N ≤ 0.05
c. N/n ≤ 0.05
d. n/N > 0.05 - ANSWER: b. n/N ≤ 0.05
A sample statistic, such as x bar , that estimates the value of the corresponding
population parameter is known as a:
a. population parameter
b. point estimator
c. Both a parameter and a population parameter are correct.
d. parameter - ANSWER: b. point estimator
The standard deviation of xbar is referred to as the
a. standard error of the mean
b. standard x
c. sample standard mean
d. sample mean deviation - ANSWER: a. standard error of the mean
Which of the following is(are) point estimator(s)?
a. σ
b. μ
c. s
d. All of these answers are correct. - ANSWER: c. s
A probability distribution for all possible values of a sample statistic is known as a
a. parameter
b. sample statistic
c. sampling distribution
d. simple random sample - ANSWER: c. sampling distribution
A population has a mean of 180 and a standard deviation of 24. A sample of 64
observations will be taken. The probability that the mean from that sample will be
between 183 and 186 is
a. 0.8185
b. 0.1359
c. 0.4772
d. 0.3413 - ANSWER: b. 0.1359
,1. st. error: 24/sqrt(64) = 3
2. z value (upper): (186-180)/3 = 2
3. Norm.s.dist(1, true) = .9772
4. z value (lower): (183-180)/3= 1
5.Norm.s.dist(-1,true)= .8413
6. 0.9772-.8413=0.1359
The basis for using a normal probability distribution to approximate the sampling
distribution of xbar and pbar is:
a. the empirical rule
b. the central limit theorem
c. Chebyshev's theorem
d. Bayes' theorem - ANSWER: b. the central limit theorem
A finite population correction factor is needed in computing the standard deviation
of the sampling distribution of sample means:
a. whenever the sample size is less than 5% of the population size
b. whenever the population is infinite
c. whenever the sample size is more than 5% of the population size
d. The correction factor is not necessary if the population has a normal distribution -
ANSWER: c. whenever the sample size is more than 5% of the population size
A sample of 66 observations will be taken from a process (an infinite population).
The population proportion equals 0.12. The probability that the sample proportion
will be less than 0.1768 is
a. 0.4222
b. 0.0778
c. 0.9222
d. 0.0568 - ANSWER: c. 0.9222
1. Mean of the sample proportions = 0.12
2. St. dev. of pbar = sqrt [ p(1-p) / n] = sqrt [ (0.12)(1-.12) / 66] = .04
μ = 0.12
σ = 0.04
3. standardize x to z = (x - μ) / σ = (0.1768-0.12) / 0.04 = 1.42
4. norm.s.dist(1.42,true) = 0.9222
A population has a mean of 53 and a standard deviation of 21. A sample of 49
observations will be taken. The probability that the sample mean will be greater than
57.95 is
a. 0
b. .0495
c. .4505
d. None of the alternative answers is correct. - ANSWER: b. .0495
1. 21/sqrt(49)=3
2. 57.93-53=4.95
, 3. 4.95/3 = 1.65
4.norm.s.dist(1.65,true) = .9505
5. 1-.9505= .0495
A numerical measure from a sample, such as a sample mean, is known as
a. a parameter
b. a statistic
c. the central limit theorem
d. the mean deviation - ANSWER: b. a statistic
T/F
Sampling is used to make an inference or answer a research question about a
population - ANSWER: True
T/F
In a simple random sample, when sampling a infinite population, you can use the
RAND excel function. - ANSWER: False
The population that you want to make inferences about when sampling is the
a. Sample population
b. Inferenced sample
c. Target population
d. Judgmental sample - ANSWER: c. Target population
A numerical characteristic of a population, such as the population mean, is known as:
a. sample characteristic
b. sample statistic
c. simple sample
d. parameter - ANSWER: d. parameter
The sample statistic, such as the sample mean, or the sample standard deviation is
known as:
a. Standard error
b. Sample statistic
c. point estimator
d. target estimator - ANSWER: c. point estimator
The standard deviation of a point estimator is:
a. Standard error
b. Sample error
c. Population error
d. Unbiased error - ANSWER: a. Standard error
