WGU C955 Applied Probability and statistics Exam
102 Questions with Verified Answers
Pie chart - CORRECT ANSWER numerical measure: percentages best used When
displaying categories as parts of the whole
Bar chart (bar graph) - CORRECT ANSWER Category counts or frequencies best
used when displaying counts or frequencies for each category individually
Dot Plot - CORRECT ANSWER 5-number summary (max, Q1, median, Q3, max)
Smaller data set; useful to display the distribution and
show gaps and outliers (quantitative)
Stem Plot (stem-and-leaf plot) - CORRECT ANSWER 5-number summary (max, Q1,
median, Q3, max)
Smaller data sets; useful to display distributions and
potential outliers; has the advantage that it keeps data
values displayed. (quantitative)
Box Plot - CORRECT ANSWER 5-number summary (max,
Q1, median, Q3, max) Larger data sets; shows the
5-number summary, shows spread; ignores individual
data values and the number of values (allowing to
compare sets of different sizes)
,Histogram - CORRECT ANSWER Based on the shape of the
distribution, uses mean + standard deviation OR
median + IQR to describe center and spread
Larger data sets; shows shapes of distribution and
potential outliers; ignores the individual data values
slope-intercept form - CORRECT ANSWER y = mx + b, where m is slope of the line
and b is the y-intercept.
Standard Deviation Rule: - CORRECT ANSWER (68-95-99.7 Rule)
68% of the data is within 1 standard deviation of the mean.
95% of the data is within 2 standard deviations of the mean.
99.7% of the data is within 3 standard deviations of the mean
positive correlation - CORRECT ANSWER scatterplot reveals an "uphill trend." As
the explanatory variable increases, the response variable increases.
Negative Correlation - CORRECT ANSWER scatterplot reveals a "downhill trend."
As the explanatory variable increases, the response variable decreases.
No Correlation - CORRECT ANSWER scatterplot reveals no trend between the
variables
, Correlation Coefficient (r) - CORRECT ANSWER measures the direction and
strength of the linear relationship between the variables.
The closer r is to +1, the stronger the positive correlation.
The closer r is to -1, the stronger the negative correlation.
The closer r is to 0, the weaker the correlation.
y=-0.082x+11 - CORRECT ANSWER Using the linear regression we can predict that
the monthly rent, y, for a home 50 miles from the center will be about:
𝑦=−0.082(50)+11=−4.1+11=6.9 or $690.
Probability - CORRECT ANSWER Probability is the chance of an event occurring
and can be expressed as a percentage, decimal, or fraction.
0% probability - Impossible
More than 0%, but less than 40% probability - Unlikely
40% to 60% probability - As likely as unlikely
more than 60%, but less than 100% probability - Likely
100% probability - Certain
Theoretical Probability - CORRECT ANSWER Number of outcomes with the desired
event over Total number of outcomes rolling two 6 sided dice : 4/36
P(A or B) - CORRECT ANSWER represents the probability that event A will occur, or
event B will occur, or both A and B will occur. (we add) OR Rule (General Addition)
▪ P(A or B) = P(A) + P(B) - P(A and B)
102 Questions with Verified Answers
Pie chart - CORRECT ANSWER numerical measure: percentages best used When
displaying categories as parts of the whole
Bar chart (bar graph) - CORRECT ANSWER Category counts or frequencies best
used when displaying counts or frequencies for each category individually
Dot Plot - CORRECT ANSWER 5-number summary (max, Q1, median, Q3, max)
Smaller data set; useful to display the distribution and
show gaps and outliers (quantitative)
Stem Plot (stem-and-leaf plot) - CORRECT ANSWER 5-number summary (max, Q1,
median, Q3, max)
Smaller data sets; useful to display distributions and
potential outliers; has the advantage that it keeps data
values displayed. (quantitative)
Box Plot - CORRECT ANSWER 5-number summary (max,
Q1, median, Q3, max) Larger data sets; shows the
5-number summary, shows spread; ignores individual
data values and the number of values (allowing to
compare sets of different sizes)
,Histogram - CORRECT ANSWER Based on the shape of the
distribution, uses mean + standard deviation OR
median + IQR to describe center and spread
Larger data sets; shows shapes of distribution and
potential outliers; ignores the individual data values
slope-intercept form - CORRECT ANSWER y = mx + b, where m is slope of the line
and b is the y-intercept.
Standard Deviation Rule: - CORRECT ANSWER (68-95-99.7 Rule)
68% of the data is within 1 standard deviation of the mean.
95% of the data is within 2 standard deviations of the mean.
99.7% of the data is within 3 standard deviations of the mean
positive correlation - CORRECT ANSWER scatterplot reveals an "uphill trend." As
the explanatory variable increases, the response variable increases.
Negative Correlation - CORRECT ANSWER scatterplot reveals a "downhill trend."
As the explanatory variable increases, the response variable decreases.
No Correlation - CORRECT ANSWER scatterplot reveals no trend between the
variables
, Correlation Coefficient (r) - CORRECT ANSWER measures the direction and
strength of the linear relationship between the variables.
The closer r is to +1, the stronger the positive correlation.
The closer r is to -1, the stronger the negative correlation.
The closer r is to 0, the weaker the correlation.
y=-0.082x+11 - CORRECT ANSWER Using the linear regression we can predict that
the monthly rent, y, for a home 50 miles from the center will be about:
𝑦=−0.082(50)+11=−4.1+11=6.9 or $690.
Probability - CORRECT ANSWER Probability is the chance of an event occurring
and can be expressed as a percentage, decimal, or fraction.
0% probability - Impossible
More than 0%, but less than 40% probability - Unlikely
40% to 60% probability - As likely as unlikely
more than 60%, but less than 100% probability - Likely
100% probability - Certain
Theoretical Probability - CORRECT ANSWER Number of outcomes with the desired
event over Total number of outcomes rolling two 6 sided dice : 4/36
P(A or B) - CORRECT ANSWER represents the probability that event A will occur, or
event B will occur, or both A and B will occur. (we add) OR Rule (General Addition)
▪ P(A or B) = P(A) + P(B) - P(A and B)
