BUAL 2650 Final Exam Review - Gupta
Study online at https://quizlet.com/_cgol29
1. It is appropriate to use the uniform distribution to relative frequencies of all
describe a continuous random variable x when possible values of x are
about the same.
2. The normal approximation of the binomial distribu- np e5 and n(1 − p) e5.
tion is appropriate when
3. The fill weight of a certain brand of adult cereal is the fill weight is less than
normally distributed with a mean of 910 grams and 910 grams.
a standard deviation of 5 grams. We calculated the
value of z for a specific box of this brand of cereal,
and the z value was negative. This negative z value
indicates that
4. Which of the following statements is not a property of 95.44 percent of all pos-
the normal probability distribution? sible observed values of
the random variable x are
within plus or minus three
standard deviations of the
population mean.
5. If the random variable x is normally distributed, ______ 99.73
percent of all possible observed values of x will be
within three standard deviations of the mean.
6. The z value tells us the number of ________ that a value standard deviations
of x is from the mean.
7. A continuous probability distribution having a rectan- uniform
gular shape, where the probability is evenly distrib-
uted over an interval of numbers is a(n) ________ dis-
tribution.
, BUAL 2650 Final Exam Review - Gupta
Study online at https://quizlet.com/_cgol29
8. The specific shape of each normal distribution is de- mean, standard deviation.
termined by its ________ and ________.
9. The area under the curve of a valid continuous prob- equal 1
ability distribution must ________.
10. ________ values of the standard deviation result in a Larger
normal curve that is wider and flatter.
11. The mean of a standard normal distribution is always 0
equal to ________.
12. Given that the length an athlete throws a hammer .1587
is a normal random variable with mean 50 feet and
standard deviation 5 feet, what is the probability he Z = (55 − 50)/5 = 1
throws it no less than 55 feet? P(X e55) = 1 − .8412 =
.1587
13. What is the probability that a standard normal ran- .3814
dom variable will be between .3 and 3.2?
14. For nonnormal populations, as the sample size (n) increases, normal
________, the distribution of sample means approaches
a(n) ________ distribution.
15. ________ says that if the sample size is sufficiently large, The Central Limit Theorem
then the sample means are approximately normally
distributed.
16. Find P(x̅ < 35) if μ = 40, σx = 16, n = 16. .1056
17. Packages of sugar bags for Sweeter Sugar Inc. have .0668
an average weight of 16 ounces and a standard devi-
ation of .2 ounces. The weights of the sugar packages
, BUAL 2650 Final Exam Review - Gupta
Study online at https://quizlet.com/_cgol29
are normally distributed. What is the probability that
16 randomly selected packages will have a weight in
excess of 16.075 ounces?
18. Find P(x̅ > 172), if μ = 175 and σ2 (variance) = 9. .8413
z=(172 − 175)/9--
=−1P(x>172)=1.00 −
.1587
19. The exact spread of the t distribution depends on the number of degrees of
________. freedom
20. When the population is normally distributed, popula- the t distribution.
tion standard deviation σ is unknown, and the sample
size is n = 15, the confidence interval for the popula-
tion mean μ is based on
21. As the standard deviation (σ) decreases, the width of decreases
the confidence interval ________.
22. A confidence interval for the population mean is an sample mean
interval constructed around the ________.
23. In a manufacturing process, a random sample of 9 2.8140 to 3.1860
manufactured bolts has a mean length of 3 inches [x̅ ± tα/2, n−1(s/n−−)]=
with a variance of .09 and is normally distributed. [3±1.86(.3/3)]=[3±.186]=[2.81
What is the 90 percent confidence interval for the true 3.186]
mean length of the manufactured bolt?
24. In a manufacturing process, a random sample of 36 2.864 to 3.136
manufactured bolts has a mean length of 3 inches [x±tα/2,n−1(s/n−−-
with a standard deviation of .3 inches. What is the 99 )]=[3±2.719(.3/6)]=[3±.136]=[
3.136]
Study online at https://quizlet.com/_cgol29
1. It is appropriate to use the uniform distribution to relative frequencies of all
describe a continuous random variable x when possible values of x are
about the same.
2. The normal approximation of the binomial distribu- np e5 and n(1 − p) e5.
tion is appropriate when
3. The fill weight of a certain brand of adult cereal is the fill weight is less than
normally distributed with a mean of 910 grams and 910 grams.
a standard deviation of 5 grams. We calculated the
value of z for a specific box of this brand of cereal,
and the z value was negative. This negative z value
indicates that
4. Which of the following statements is not a property of 95.44 percent of all pos-
the normal probability distribution? sible observed values of
the random variable x are
within plus or minus three
standard deviations of the
population mean.
5. If the random variable x is normally distributed, ______ 99.73
percent of all possible observed values of x will be
within three standard deviations of the mean.
6. The z value tells us the number of ________ that a value standard deviations
of x is from the mean.
7. A continuous probability distribution having a rectan- uniform
gular shape, where the probability is evenly distrib-
uted over an interval of numbers is a(n) ________ dis-
tribution.
, BUAL 2650 Final Exam Review - Gupta
Study online at https://quizlet.com/_cgol29
8. The specific shape of each normal distribution is de- mean, standard deviation.
termined by its ________ and ________.
9. The area under the curve of a valid continuous prob- equal 1
ability distribution must ________.
10. ________ values of the standard deviation result in a Larger
normal curve that is wider and flatter.
11. The mean of a standard normal distribution is always 0
equal to ________.
12. Given that the length an athlete throws a hammer .1587
is a normal random variable with mean 50 feet and
standard deviation 5 feet, what is the probability he Z = (55 − 50)/5 = 1
throws it no less than 55 feet? P(X e55) = 1 − .8412 =
.1587
13. What is the probability that a standard normal ran- .3814
dom variable will be between .3 and 3.2?
14. For nonnormal populations, as the sample size (n) increases, normal
________, the distribution of sample means approaches
a(n) ________ distribution.
15. ________ says that if the sample size is sufficiently large, The Central Limit Theorem
then the sample means are approximately normally
distributed.
16. Find P(x̅ < 35) if μ = 40, σx = 16, n = 16. .1056
17. Packages of sugar bags for Sweeter Sugar Inc. have .0668
an average weight of 16 ounces and a standard devi-
ation of .2 ounces. The weights of the sugar packages
, BUAL 2650 Final Exam Review - Gupta
Study online at https://quizlet.com/_cgol29
are normally distributed. What is the probability that
16 randomly selected packages will have a weight in
excess of 16.075 ounces?
18. Find P(x̅ > 172), if μ = 175 and σ2 (variance) = 9. .8413
z=(172 − 175)/9--
=−1P(x>172)=1.00 −
.1587
19. The exact spread of the t distribution depends on the number of degrees of
________. freedom
20. When the population is normally distributed, popula- the t distribution.
tion standard deviation σ is unknown, and the sample
size is n = 15, the confidence interval for the popula-
tion mean μ is based on
21. As the standard deviation (σ) decreases, the width of decreases
the confidence interval ________.
22. A confidence interval for the population mean is an sample mean
interval constructed around the ________.
23. In a manufacturing process, a random sample of 9 2.8140 to 3.1860
manufactured bolts has a mean length of 3 inches [x̅ ± tα/2, n−1(s/n−−)]=
with a variance of .09 and is normally distributed. [3±1.86(.3/3)]=[3±.186]=[2.81
What is the 90 percent confidence interval for the true 3.186]
mean length of the manufactured bolt?
24. In a manufacturing process, a random sample of 36 2.864 to 3.136
manufactured bolts has a mean length of 3 inches [x±tα/2,n−1(s/n−−-
with a standard deviation of .3 inches. What is the 99 )]=[3±2.719(.3/6)]=[3±.136]=[
3.136]
