Deck 3: Descriptive Statistics: Numerical Methods

Question 1

The mode is the measurement in a sample or population that occurs most frequently.

Answer 1

True

Question 2

The population mean is the point estimate of the sample mean.

Answer 2

False

Question 3

A normal population has 99.73 percent of the population measurements within _____ standard deviations of the mean.

A)One
B)Two
C)Three
D)Four

Answer 3

C

Question 4

An independent variable is a predictor variable that can be used to describe,predict,or control a dependent variable.

Question 5

The median is the measure of central tendency that divides a population or sample into four equal parts.

Question 6

A numeric characteristic of a sample is a

A)Mean
B)Variance
C)Statistic
D)Parameter

Question 7

The median is said to be resistant to extreme values.

Question 8

The population mean is the average of the population measurements.

Question 9

In a given data set the 25^th percentile is _______________ equal the lower hinge.

A)Always
B)Sometimes
C)Never

Question 10

Range is a better measure of variation than standard deviation.

Question 11

It is appropriate to use the Empirical Rule to describe a population that is extremely skewed.

Question 12

If there are 7 classes in a frequency distribution then the fourth class will always contain the median.

Question 13

All of the following are measures of central tendency except the

A)Range
B)Mode
C)Mean
D)Median

Question 14

In a symmetric population,the median equals the mode.

Question 15

The median is the value below which and above which approximately 50 percent of the measurements lie.

Question 16

The population variance is the average of the squared deviations of the individual population measurements from the population mean.

Question 17

The range of the measurement is the largest measurement plus the small measurement.

Question 18

Which percentile describes the third quartile,Q3?

A)25^th
B)50^th
C)75^th
D)100^th

Question 19

Which percentile describes the first quartile,Q1?

A)25^th
B)50^th
C)75^th
D)100^th

Question 20

Which of the following is influenced the least by the occurrence of extreme values in a sample?

A)Mean
B)Median
C)Mode
D)Geometric mean
E)Weighted mean

Question 21

A disadvantage of using grouping (a frequency table)with sample data is that:

A)Calculations involving central tendency and variation are more complicated than central tendency and variation calculations based on ungrouped data.
B)The descriptive statistics are less precise than the descriptive statistics obtained using ungrouped data.
C)The interpretation of the grouped data descriptive statistics is meaningless.
D)It is much more difficult to summarize the information than it is with the ungrouped data.

Question 22

In a hearing test,subjects estimate the loudness (in decibels)of sound,and the results are: 68,67,70,71,68,75,68,62,80,73,68 What is the mode?

A)70
B)75
C)68
D)71
E)80

Question 23

The company financial officer was interested in the average cost of PCs that had been purchased in the past six months.A random sample of the price of 10 computers was taken with the following results: $3,250,$1,127,$2,995,$3,250,$3,445,$3,449,$1,482,$6,120,$3,009,$4,000 What is the mode?

A)3447
B)3213
C)3250
D)6120
E)3445

Question 24

As a measure of variation,the sample _________ is easy to understand and compute.It is based on the two extreme values and is therefore a highly unstable measure.

A)Range
B)Standard deviation
C)Variance
D)Interquartile range
E)Coefficient of variation

Question 25

In a statistic class,10 scores were randomly selected with the following results were obtained: 74,73,77,77,71,68,65,77,67,66 What is the mode?

A)71.5
B)72.0
C)77.0
D)71.0
E)73.0

Question 26

The local amusement park was interested in the average wait time at their most popular roller coaster at the peak park time (2 p.m. ).They selected 13 patrons and had them get in line between 2 and 3 p.m.Each was given a stop watch to record the time they spent in line.The times recorded were as follows (in minutes): 118,124,108,116,99,120,148,118,119,121,45,130,118 What is the median?

A)114.15
B)118
C)148
D)45
E)115.5

Question 27

Quality control is an important issue at ACME Company which manufactures light bulbs.In order to conduct testing of the life hours of their light bulbs,they randomly sampled nine light bulbs and measured how many hours they lasted.378,361,350,375,200,391,375,368,321 What is the mean?

A)375
B)368
C)389.9
D)200
E)346.6

Question 28

If a population distribution is skewed to the right,then,given a random sample from that population,one would expect that the

A)median would be greater than the mean.
B)mode would be equal to the mean.
C)median would be less than the mean.
D)median would be equal to the mean.

Question 29

In a hearing test,subjects estimate the loudness (in decibels)of sound,and the results are: 68,67,70,71,68,75,68,62,80,73,68 What is the median?

A)70
B)75
C)68
D)71
E)80

Question 30

In a hearing test,subjects estimate the loudness (in decibels)of sound,and the results are: 68,67,70,71,68,75,68,62,80,73,68 What is the mean?

A)70
B)75
C)68
D)71
E)80

Question 31

The local amusement park was interested in the average wait time at their most popular roller coaster at the peak park time (2 p.m. ).They selected 13 patrons and had them get in line between 2 and 3 p.m.Each was given a stop watch to record the time they spent in line.The times recorded were as follows (in minutes): 118,124,108,116,99,120,148,118,119,121,45,130,118 What is the mode?

A)114.15
B)118
C)148
D)45
E)115.5

Question 32

In a statistic class,10 scores were randomly selected with the following results were obtained: 74,73,77,77,71,68,65,77,67,66 What is the mean?

A)71.5
B)72.0
C)77.0
D)71.0
E)73.0

Question 33

When using the Chebyshev's theorem to obtain the bounds for a 99.73 percent of the values in a population,the interval generally will be ___________ the interval obtained for the same percentage if normal distribution is assumed (empirical rule).

A)Shorter than
B)Wider than
C)The same as

Question 34

The local amusement park was interested in the average wait time at their most popular roller coaster at the peak park time (2 p.m. ).They selected 13 patrons and had them get in line between 2 and 3 p.m.Each was given a stop watch to record the time they spent in line.The times recorded were as follows (in minutes): 118,124,108,116,99,120,148,118,119,121,45,130,118 What is mean?

A)114.15
B)118
C)148
D)45
E)115.5

Question 35

The company financial officer was interested in the average cost of PCs that had been purchased in the past six months.A random sample of the price of 10 computers was taken with the following results: $3,250,$1,127,$2,995,$3,250,$3,445,$3,449,$1,482,$6,120,$3,009,$4,000 What is the median?

A)3447
B)3213
C)3250
D)6120
E)3445

Question 36

If the mean,median,and mode for a given population all equal 25,then we Know that its distribution is

A)Bimodal
B)Skewed to the right
C)Symmetric
D)Skewed to the left

Question 37

A quantity that measures the variation of a population or a sample relative to its mean is called the

A)Range
B)Standard deviation
C)Coefficient of variation
D)Variance
E)Interquartile range

Question 38

In a statistic class,10 scores were randomly selected with the following results were obtained: 74,73,77,77,71,68,65,77,67,66 What is the median?

A)71.5
B)72.0
C)77.0
D)71.0
E)73.0

Question 39

The company financial officer was interested in the average cost of PCs that had been purchased in the past six months.A random sample of the price of 10 computers was taken with the following results: $3,250,$1,127,$2,995,$3,250,$3,445,$3,449,$1,482,$6,120,$3,009,$4,000 What is the mean?

A)3447
B)3213
C)3250
D)6120
E)3445

Question 40

If one intends to compare the relative variation between two samples involving two different quantitative variables with different measurement scales,then the most appropriate way is to compare the two samples:

A)Standard deviations
B)Variances
C)Coefficient of variations
D)Ranges
E)Interquartile ranges

Question 41

In a statistic class,10 scores were randomly selected with the following results were obtained (mean = 71.5): 74,73,77,77,71,68,65,77,67,66 What is the standard deviation?

A)22.72
B)12.00
C)4.77
D)516.20
E)144.00

Question 42

According to Chebyshev's theorem,how many standard deviations from the range would include at least 80% of the values?

A)5.0
B)2.2
C)2.5
D)1.6
E)2.0

Question 43

Find the z-score for an IQ test score of 142 when the mean is 100 and the standard deviation is 15.

A)42
B)2.8
C)18.78
D)1.27
E)-2.8

Question 44

According to Chebyshev's Theorem,at least what proportion of the data will be within for: k = 3.2

A)90%
B)95%
C)84%
D)97%
E)10%

Question 45

According to a survey of the top 10 employers in a major city in the Midwest,a worker spends an average of 413 minutes a day on the job.Suppose the standard deviation is 26.8 minutes and the time spent is approximately a normal distribution. What are the times that approximately 95.44% of all workers will fall?

A)[387.5 438.5]
B)[386.2 439.8]
C)[372.8 453.2]
D)[359.4 466.6]
E)[332.6 493.4]

Question 46

According to a survey of the top 10 employers in a major city in the Midwest,a worker spends an average of 413 minutes a day on the job.Suppose the standard deviation is 26.8 minutes and the time spent is approximately a normal distribution. What are the times that approximately 68.26% of all workers will fall?

A)[394.8 431.2]
B)[386.2 439.8]
C)[372.8 453.2]
D)[359.4 466.6]
E)[332.6 493.4]

Question 47

Find the z-score for an IQ test score of 92 when the mean is 100 and the standard deviation is 15.

A)0.53
B)0.77
C)-0.77
D)-0.53
E)-8.00

Question 48

According to Chebyshev's Theorem,at least what proportion of the data will be within for: k = 2

A)68%
B)50%
C)25%
D)75%
E)34%

Question 49

Quality control is an important issue at ACME Company which manufactures light bulbs.In order to conduct testing of the life hours of their light bulbs,they randomly sampled nine light bulbs and measured how many hours they lasted.378,361,350,375,200,391,375,368,321 What is the mode?

A)375
B)368
C)389.9
D)200
E)346.6

Question 50

According to Chebyshev's Theorem,at least what proportion of the data will be within for: k = 2.5

A)16%
B)40%
C)68%
D)60%
E)84%

Question 51

Using Chebyshev's Rule,find the interval that contains at least 93.75% of all measurements when mean = 2.549 and s = 1.828.

A)[-2.935 8.033]
B)[-1.107 6.205]
C)[-26.699 31.797]
D)[2.435 2.663]
E)[-4.763 9.861]

Question 52

According to a survey of the top 10 employers in a major city in the Midwest,a worker spends an average of 413 minutes a day on the job.Suppose the standard deviation is 26.8 minutes and the time spent is approximately a normal distribution. What are the times that approximately 99.73% of all workers will fall?

A)[305.8 520.2]
B)[386.2 439.8]
C)[372.8 453.2]
D)[359.4 466.6]
E)[332.6 493.4]

Question 53

According to Chebyshev's Theorem,at least what proportion of the data will be within for: k = 1.6

A)39%
B)58%
C)68%
D)61%
E)92%

Question 54

In a statistic class,10 scores were randomly selected with the following results were obtained (mean = 71.5): 74,73,77,77,71,68,65,77,67,66 What is the range?

A)22.72
B)12.00
C)4.77
D)516.20
E)144.00

Question 55

Find the z-score for an IQ test score of 125 when the mean is 100 and the standard deviation is 15.

A)25
B)1.1
C)1.67
D)-1.1
E)-1.67

Question 56

Quality control is an important issue at ACME Company which manufactures light bulbs.In order to conduct testing of the life hours of their light bulbs,they randomly sampled nine light bulbs and measured how many hours they lasted.378,361,350,375,200,391,375,368,321 What is the median?

A)375
B)368
C)389.9
D)200
E)346.6

Question 57

Find the coefficient of variation for IQ tests with a mean of 100 and a standard deviation of 15.

A)15.0
B)6.7
C)0.15
D)1.5
E)67

Question 58

In a statistic class,10 scores were randomly selected with the following results were obtained (mean = 71.5): 74,73,77,77,71,68,65,77,67,66 What is the variance?

A)22.72
B)12.00
C)4.77
D)516.20
E)144.00

Question 59

In a hearing test,subjects estimate the loudness (in decibels)of sound,and the results are (mean = 70): 68,67,70,71,68,75,68,62,80,73,68 What is the range?

A)18
B)4.73
C)22.40
D)324
E)6.76

Question 60

Find the z-score for an IQ test score of 118 when the mean is 100 and the standard deviation is 15.

A)1.2
B)1.0
C)18.0
D)-1.03
E)-1.2

Question 61

In a hearing test,subjects estimate the loudness (in decibels)of sound,and the results are (mean = 70): 68,67,70,71,68,75,68,62,80,73,68 What is the variance?

A)18
B)4.73
C)22.40
D)324
E)6.76

Question 62

Quality control is an important issue at ACME Company which manufactures light bulbs.In order to conduct testing of the life hours of their light bulbs,they randomly sampled nine light bulbs and measured how many hours they lasted (mean = 346.6).378,361,350,375,200,391,375,368,321 What is the variance?

A)342.43
B)3424.3
C)58.5
D)191
E)10609

Question 63

Quality control is an important issue at ACME Company which manufactures light bulbs.In order to conduct testing of the life hours of their light bulbs,they randomly sampled nine light bulbs and measured how many hours they lasted (mean = 346.6).378,361,350,375,200,391,375,368,321 What is the range?

A)342.43
B)3424.3
C)58.5
D)191
E)10609

Question 64

The local amusement park was interested in the average wait time at their most popular roller coaster at the peak park time (2 p.m. ).They selected 13 patrons and had them get in line between 2 and 3 p.m.Each was given a stop watch to record the time they spent in line.The times recorded were as follows (in minutes)(mean = 114.15): 118,124,108,116,99,120,148,118,119,121,45,130,118 What is the variance?

A)103
B)23.62
C)557.97
D)128.8
E)115

Question 65

Quality control is an important issue at ACME Company which manufactures light bulbs.In order to conduct testing of the life hours of their light bulbs,they randomly sampled nine light bulbs and measured how many hours they lasted (mean = 346.6).378,361,350,375,200,391,375,368,321 What is the standard deviation?

A)342.43
B)3424.3
C)58.5
D)191
E)10609

Question 66

In a statistic class,10 scores were randomly selected with the following results were obtained: 74,73,77,77,71,68,65,77,67,66 What is the 90^th percentile?

A)77
B)73
C)74
D)67
E)65.9

Question 67

The local amusement park was interested in the average wait time at their most popular roller coaster at the peak park time (2 p.m. ).They selected 13 patrons and had them get in line between 2 and 3 p.m.Each was given a stop watch to record the time they spent in line.The times recorded were as follows (in minutes)(mean = 114.15): 118,124,108,116,99,120,148,118,119,121,45,130,118 What is the range?

A)103
B)23.62
C)557.97
D)128.8
E)115

Question 68

The company financial officer was interested in the average cost of PCs that had been purchased in the past six months.A random sample of the price of 10 computers was taken with the following results (mean = $3,213): $3,250,$1,127,$2,995,$3,250,$3,445,$3,449,$1,482,$6,120,$3,009,$4,000 What is the range?

A)1359
B)4993
C)1846575
D)3587
E)1976454

Question 69

In a statistic class,10 scores were randomly selected with the following results were obtained:74,73,77,77,71,68,65,77,67,66 What is the IQR?

A)12.00
B)5.25
C)10.25
D)5.00
E)11.00

Question 70

In a statistic class,10 scores were randomly selected with the following results were obtained: 74,73,77,77,71,68,65,77,67,66 What is the third quartile?

A)65.9
B)67.3
C)66.75
D)73.85
E)77.0

Question 71

The company financial officer was interested in the average cost of PCs that had been purchased in the past six months.A random sample of the price of 10 computers was taken with the following results (mean = $3,213): $3,250,$1,127,$2,995,$3,250,$3,445,$3,449,$1,482,$6,120,$3,009,$4,000 What is the variance?

A)1359
B)4993
C)1846575
D)3587
E)1976454

Question 72

In a statistic class,10 scores were randomly selected with the following results were obtained: 74,73,77,77,71,68,65,77,67,66 What are the inner fences?

A)15.375,30.75
B)82.125,92.375
C)97.50,107.75
D)51.375,92.375
E)35.95,107.75

Question 73

In a statistic class,10 scores were randomly selected with the following results were obtained: 74,73,77,77,71,68,65,77,67,66 What is the first quartile?

A)65.9
B)67.3
C)66.75
D)73.85
E)77.0

Question 74

In a hearing test,subjects estimate the loudness (in decibels)of sound,and the results are (mean = 70): 68,67,70,71,68,75,68,62,80,73,68 What is the standard deviation?

A)18
B)4.73
C)22.40
D)324
E)6.76

Question 75

The company financial officer was interested in the average cost of PCs that had been purchased in the past six months.A random sample of the price of 10 computers was taken with the following results (mean = $3,213): $3,250,$1,127,$2,995,$3,250,$3,445,$3,449,$1,482,$6,120,$3,009,$4,000 What is the standard deviation?

A)1359
B)4993
C)1846575
D)3587
E)1976454

Question 76

In a statistic class,10 scores were randomly selected with the following results were obtained: 74,73,77,77,71,68,65,77,67,66 What are the outer fences?

A)15.375,30.75
B)51.375,92.375
C)35.95,107.75
D)82.125,92.375
E)97.50,107.75

Question 77

In a statistic class,10 scores were randomly selected with the following results were obtained: 74,73,77,77,71,68,65,77,67,66 What is the 65^th percentile?

A)65.9
B)67.3
C)66.75
D)73.85
E)77.0

Question 78

In a statistic class,10 scores were randomly selected with the following results were obtained: 74,73,77,77,71,68,65,77,67,66 What is the 10^th percentile?

A)65.9
B)67.3
C)66.75
D)73.85
E)77.0

Question 79

The local amusement park was interested in the average wait time at their most popular roller coaster at the peak park time (2 p.m. ).They selected 13 patrons and had them get in line between 2 and 3 p.m.Each was given a stop watch to record the time they spent in line.The times recorded were as follows (in minutes)(mean = 114.15): 118,124,108,116,99,120,148,118,119,121,45,130,118 What is the standard deviation?

A)103
B)23.62
C)557.97
D)128.8
E)115

Question 80

In a hearing test,subjects estimate the loudness (in decibels)of sound,and the results are;68,67,70,71,68,75,68,62,80,73,68 What is the 90^th percentile?

A)73
B)68
C)70.5
D)67
E)75