6/29/2020 Sophia :: Welcome
Score 21/25
You passed this Milestone
21 questions were answered correctly.
MILESTONE
4 questions were answered incorrectly.
1
Sukie interviewed 125 employees at her company and discovered that 21 of them planned to take an extended
vacation next year. She finds that the proportion of people taking extended vacations nationally is 15%.
The z statistic for this data is __________.
-0.56
-0.45
0.56
0.45
RATIONALE
Your text here
https://www.sophia.org/spcc/introduction-to-statistics-2/milestone_take_feedbacks/4325846 1/19
,6/29/2020 Sophia :: Welcome
To make things a little easier, let's first note the denominator
We can now note that
Finally, subbing all in we find
CONCEPT
Z-Test for Population Proportions
2
Jesse takes two data points from the weight and feed cost data set to calculate a slope, or average rate of change.
A rat weighs 3.5 pounds and costs $4.50 per week to feed, while a Beagle weighs 30 pounds and costs $9.20 per
week to feed.
Using weight as the explanatory variable, what is the slope of the line between these two points? Answer
choices are rounded to the nearest hundredth.
$0.31 / lb.
$1.60 / lb.
$5.64 / lb.
$0.18 / lb.
RATIONALE
In order to get slope, we can use the formula: .
Using the information provided, the two points are: (3.5 lb., $4.50) and (30 lb., $9.20). We can note that:
CONCEPT
https://www.sophia.org/spcc/introduction-to-statistics-2/milestone_take_feedbacks/4325846 2/19
, 6/29/2020 Sophia :: Welcome
Linear Equation Algebra Review
3
A research team conducts a survey to determine the area of land used for farming in Iowa. The team randomly
selects house addresses and sends the survey by mail.
Which type of sampling method is the research team using?
Simple random sampling
Systematic random sampling
Multi-stage sampling
Cluster sampling
RATIONALE
By choosing randomly from the house addresses all households should have an equal chance of being chosen.
This would make it a simple random sample.
CONCEPT
Simple Random and Systematic Random Sampling
4
Katherine, Jonathan, and Ryan went bowling. Afterwards, two of them decided to make bar graphs to plot their
scores.
Who made Graph 2, and why?
Jonathan, because he wanted to make the scores appear reasonably close.
https://www.sophia.org/spcc/introduction-to-statistics-2/milestone_take_feedbacks/4325846 3/19
Score 21/25
You passed this Milestone
21 questions were answered correctly.
MILESTONE
4 questions were answered incorrectly.
1
Sukie interviewed 125 employees at her company and discovered that 21 of them planned to take an extended
vacation next year. She finds that the proportion of people taking extended vacations nationally is 15%.
The z statistic for this data is __________.
-0.56
-0.45
0.56
0.45
RATIONALE
Your text here
https://www.sophia.org/spcc/introduction-to-statistics-2/milestone_take_feedbacks/4325846 1/19
,6/29/2020 Sophia :: Welcome
To make things a little easier, let's first note the denominator
We can now note that
Finally, subbing all in we find
CONCEPT
Z-Test for Population Proportions
2
Jesse takes two data points from the weight and feed cost data set to calculate a slope, or average rate of change.
A rat weighs 3.5 pounds and costs $4.50 per week to feed, while a Beagle weighs 30 pounds and costs $9.20 per
week to feed.
Using weight as the explanatory variable, what is the slope of the line between these two points? Answer
choices are rounded to the nearest hundredth.
$0.31 / lb.
$1.60 / lb.
$5.64 / lb.
$0.18 / lb.
RATIONALE
In order to get slope, we can use the formula: .
Using the information provided, the two points are: (3.5 lb., $4.50) and (30 lb., $9.20). We can note that:
CONCEPT
https://www.sophia.org/spcc/introduction-to-statistics-2/milestone_take_feedbacks/4325846 2/19
, 6/29/2020 Sophia :: Welcome
Linear Equation Algebra Review
3
A research team conducts a survey to determine the area of land used for farming in Iowa. The team randomly
selects house addresses and sends the survey by mail.
Which type of sampling method is the research team using?
Simple random sampling
Systematic random sampling
Multi-stage sampling
Cluster sampling
RATIONALE
By choosing randomly from the house addresses all households should have an equal chance of being chosen.
This would make it a simple random sample.
CONCEPT
Simple Random and Systematic Random Sampling
4
Katherine, Jonathan, and Ryan went bowling. Afterwards, two of them decided to make bar graphs to plot their
scores.
Who made Graph 2, and why?
Jonathan, because he wanted to make the scores appear reasonably close.
https://www.sophia.org/spcc/introduction-to-statistics-2/milestone_take_feedbacks/4325846 3/19
