STATISTICS FINAL EXAM UPDATED
MULTIPLE CHOICE QUESTIONS AND
CORRECT ANSWERS
◉ Compute the mean, variance and standard deviation for the
following data:
2, 3, 8, 1, 1, 7, 5, 6, 10, 8
Answer: x ̅=5.1,s=3.21
◉ Compute the mean, variance and standard deviation for the
following data:
4, 2, 3, 4, 1, 0, 2, 2, 3, 4, 2, 1, 2, 3, 2, 1, 2, 3, 2, 3
Answer: x ̅=2.3,s=1.08
◉ Why is it preferable to use standard deviation as opposed to
variance in analyzing a set of data? Explain.
Answer: Answers will vary: In most cases, the unit of
measurement of the calculations you make in Statistics should
match the same unit of measurement found in the original data
set. Since the original data is in 'standard size' units, we prefer to
use standard deviation which is also in standard size units.
Variance is measured in 'units squared' and this presents a
problem since it does not match the unit of measurement for the
original data.
,◉ Define variance and explain why there are three different
formulas to compute it. When should each be applied?
Answer: 5. Answers will vary: Variance measures the spread of a
data set (in terms of distances from the mean) in square units.
Variance helps us to understand whether or not a data set is
clustered or scattered about its mean. There are three formulas to
measure it: the traditional formula for raw data which is no longer
used by many people because it is tedious to apply; the modern
formula for raw data which has replaced the traditional formula
and is generally applied to all problems involving raw data since it
is a relatively easy calculation; and finally the formula for
measuring variance for a frequency table. lol
◉ Form a frequency table for the following data:
4, 2, 3, 4, 1, 0, 2, 2, 3, 4, 2, 1, 2, 3, 2, 1, 2, 3, 2, 3
Answer:
◉ Find the mean, variance, and standard deviation for the
frequency table you found in problem #1. Compare your answer
to the solution from Assignment #1, problem #. Did you get the
same result?
Answer: X=2.3, s=1.08
◉ Compute the mean, variance and standard deviation for the
following data:
Let x = the number of telemarketing calls you have received this
week.
, xf
16
2 10
39
48
57
Answer: X=3, s=1.34
◉ Compute the mean, variance and standard deviation for the
following data:
Let x = the number of people who have eaten at a fast-food
restaurant this week.
xf
02
15
21
33
Answer: x=1.45, s=1.13
◉ 1. Compute the mean, variance and standard deviation for the
following data:
MULTIPLE CHOICE QUESTIONS AND
CORRECT ANSWERS
◉ Compute the mean, variance and standard deviation for the
following data:
2, 3, 8, 1, 1, 7, 5, 6, 10, 8
Answer: x ̅=5.1,s=3.21
◉ Compute the mean, variance and standard deviation for the
following data:
4, 2, 3, 4, 1, 0, 2, 2, 3, 4, 2, 1, 2, 3, 2, 1, 2, 3, 2, 3
Answer: x ̅=2.3,s=1.08
◉ Why is it preferable to use standard deviation as opposed to
variance in analyzing a set of data? Explain.
Answer: Answers will vary: In most cases, the unit of
measurement of the calculations you make in Statistics should
match the same unit of measurement found in the original data
set. Since the original data is in 'standard size' units, we prefer to
use standard deviation which is also in standard size units.
Variance is measured in 'units squared' and this presents a
problem since it does not match the unit of measurement for the
original data.
,◉ Define variance and explain why there are three different
formulas to compute it. When should each be applied?
Answer: 5. Answers will vary: Variance measures the spread of a
data set (in terms of distances from the mean) in square units.
Variance helps us to understand whether or not a data set is
clustered or scattered about its mean. There are three formulas to
measure it: the traditional formula for raw data which is no longer
used by many people because it is tedious to apply; the modern
formula for raw data which has replaced the traditional formula
and is generally applied to all problems involving raw data since it
is a relatively easy calculation; and finally the formula for
measuring variance for a frequency table. lol
◉ Form a frequency table for the following data:
4, 2, 3, 4, 1, 0, 2, 2, 3, 4, 2, 1, 2, 3, 2, 1, 2, 3, 2, 3
Answer:
◉ Find the mean, variance, and standard deviation for the
frequency table you found in problem #1. Compare your answer
to the solution from Assignment #1, problem #. Did you get the
same result?
Answer: X=2.3, s=1.08
◉ Compute the mean, variance and standard deviation for the
following data:
Let x = the number of telemarketing calls you have received this
week.
, xf
16
2 10
39
48
57
Answer: X=3, s=1.34
◉ Compute the mean, variance and standard deviation for the
following data:
Let x = the number of people who have eaten at a fast-food
restaurant this week.
xf
02
15
21
33
Answer: x=1.45, s=1.13
◉ 1. Compute the mean, variance and standard deviation for the
following data:
