Sophia Statistics Unit 4 Milestone
Questions Answers Rationale Latest
Summer 2021
Score 15/18
You passed this Milestone
15 questions were answered correctly.
UNIT 4 — MILESTONE 4
3 questions were answered incorrectly.
1
The table below shows the grade and reading level for 5 students.
Grade Reading Level
Student 1 2 6
Student 2 6 14
Student 3 5 12
Student 4 4 10
Student 5 1 4
For grade, the mean is 3.6 and the standard deviation is 2.1.
For reading level, the mean is 9.2 and the standard deviation is 4.1.
Using the formula below or Excel, find the correlation coefficient, r, for this set of students. Answer choices
are rounded to the nearest hundredth.
1.00
0.85
0.71
, 0.92
RATIONALE
In order to get the correlation, we can use the formula:
Correlation can be quickly calculated by using Excel. Enter the values and use the function "=CORREL(".
CONCEPT
Correlation
I need help with this question
2
This scatterplot shows the maintenance expense for a truck based on its years of service.
, The equation for least regression line to this data set is ŷ = 76.82x + 88.56.
What is the predicted value (in dollars) for maintenance expenses when a truck is 7 years old?
$549
$473
$626
$703
RATIONALE
In order to get the predicted maintenance expense when the age of the truck is 7 years, we simply substitute the value
7 in our equation for x. So we can note that:
CONCEPT
Predictions from Best-Fit Lines
I need help with this question
3
Raoul lives in Minneapolis and he is planning his spring break trip. He creates the scatterplot below to assess how
much his trip will cost.
Questions Answers Rationale Latest
Summer 2021
Score 15/18
You passed this Milestone
15 questions were answered correctly.
UNIT 4 — MILESTONE 4
3 questions were answered incorrectly.
1
The table below shows the grade and reading level for 5 students.
Grade Reading Level
Student 1 2 6
Student 2 6 14
Student 3 5 12
Student 4 4 10
Student 5 1 4
For grade, the mean is 3.6 and the standard deviation is 2.1.
For reading level, the mean is 9.2 and the standard deviation is 4.1.
Using the formula below or Excel, find the correlation coefficient, r, for this set of students. Answer choices
are rounded to the nearest hundredth.
1.00
0.85
0.71
, 0.92
RATIONALE
In order to get the correlation, we can use the formula:
Correlation can be quickly calculated by using Excel. Enter the values and use the function "=CORREL(".
CONCEPT
Correlation
I need help with this question
2
This scatterplot shows the maintenance expense for a truck based on its years of service.
, The equation for least regression line to this data set is ŷ = 76.82x + 88.56.
What is the predicted value (in dollars) for maintenance expenses when a truck is 7 years old?
$549
$473
$626
$703
RATIONALE
In order to get the predicted maintenance expense when the age of the truck is 7 years, we simply substitute the value
7 in our equation for x. So we can note that:
CONCEPT
Predictions from Best-Fit Lines
I need help with this question
3
Raoul lives in Minneapolis and he is planning his spring break trip. He creates the scatterplot below to assess how
much his trip will cost.
