Score 16/24
You passed this Milestone
16 questions were answered correctly.
UNIT 5 — MILESTONE 5
8 questions were answered incorrectly.
1
Which of the following is an example of a parameter?
Half of the receipts at the coffee shop include web address for giving feedback.
9047 out of 531,310 citizens voted in the special election for city council.
3.5% of the restaurant goers are given a survey to fill out.
All of the members of the community watch group gave their availability to volunteer over the summer.
RATIONALE
Recall a parameter comes from the entire set of interest, the
population. Since they are looking at all members of a community here, their availability to volunteer would be an
example of a parameter.
CONCEPT
Sample Statistics and Population Parameters
I need help with this question
2
A school is gathering some data on its sports teams because it was believed that the distribution of boys and girls
were evenly distributed across all the sports. This table lists the number of boys and girls participating in each
sport.
, Boys Girls
Tennis 18 30
Soccer 42 15
Swimming 12 18
Select the observed and expected frequencies for the boys participating in soccer.
Observed: 42
Expected: 22.5
Observed: 42
Expected: 24
Observed: 57
Expected: 24
Observed: 57
Expected: 22.5
RATIONALE
If we simply go to the chart then we can directly see the observed frequency for boys participating in soccer is 42.
To find the expected frequency, we need to find the number of
occurrences if the null hypothesis is true, which in this case, was that the three options are equally likely, or if the
three options were all evenly distributed.
First, add up all the options in the boys column:
If each of these three options were evenly distributed among the 72 boys, we would need to divide the total evenly
between the three options:
This means we would expect 24 boys to choose tennis, 24 boys to choose soccer, and 24 boys to choose
swimming.
CONCEPT
, Chi-Square Statistic
I need help with this question
3
Sukie interviewed 125 employees at her company and discovered that 21 of them planned to take an extended
vacation next year.
What is the 95% confidence interval for this population proportion? Answer choices are rounded to the
hundredths place.
0.11 to 0.21
0.10 to 0.23
0.16 to 0.17
0.11 to 0.16
RATIONALE
In order to get the CI we want to use the following form.
p with hat on top plus-or-minus z to the power of asterisk times square root of fraction numerator p with hat on
top q with hat on top over denominator n end fraction end root
First, we must determine the corresponding z*score for 95% Confidence Interval. Remember, this means that we
have 5% for the tails, meaning 5%, or 0.025, for each tail. Using a z-table, we can find the upper z-score by
finding (1 - 0.025) or 0.975 in the table.
This corresponding z-score is at 1.96.
We can know p with hat on top comma space q with hat on top comma space a n d space n.
So putting it all together:
You passed this Milestone
16 questions were answered correctly.
UNIT 5 — MILESTONE 5
8 questions were answered incorrectly.
1
Which of the following is an example of a parameter?
Half of the receipts at the coffee shop include web address for giving feedback.
9047 out of 531,310 citizens voted in the special election for city council.
3.5% of the restaurant goers are given a survey to fill out.
All of the members of the community watch group gave their availability to volunteer over the summer.
RATIONALE
Recall a parameter comes from the entire set of interest, the
population. Since they are looking at all members of a community here, their availability to volunteer would be an
example of a parameter.
CONCEPT
Sample Statistics and Population Parameters
I need help with this question
2
A school is gathering some data on its sports teams because it was believed that the distribution of boys and girls
were evenly distributed across all the sports. This table lists the number of boys and girls participating in each
sport.
, Boys Girls
Tennis 18 30
Soccer 42 15
Swimming 12 18
Select the observed and expected frequencies for the boys participating in soccer.
Observed: 42
Expected: 22.5
Observed: 42
Expected: 24
Observed: 57
Expected: 24
Observed: 57
Expected: 22.5
RATIONALE
If we simply go to the chart then we can directly see the observed frequency for boys participating in soccer is 42.
To find the expected frequency, we need to find the number of
occurrences if the null hypothesis is true, which in this case, was that the three options are equally likely, or if the
three options were all evenly distributed.
First, add up all the options in the boys column:
If each of these three options were evenly distributed among the 72 boys, we would need to divide the total evenly
between the three options:
This means we would expect 24 boys to choose tennis, 24 boys to choose soccer, and 24 boys to choose
swimming.
CONCEPT
, Chi-Square Statistic
I need help with this question
3
Sukie interviewed 125 employees at her company and discovered that 21 of them planned to take an extended
vacation next year.
What is the 95% confidence interval for this population proportion? Answer choices are rounded to the
hundredths place.
0.11 to 0.21
0.10 to 0.23
0.16 to 0.17
0.11 to 0.16
RATIONALE
In order to get the CI we want to use the following form.
p with hat on top plus-or-minus z to the power of asterisk times square root of fraction numerator p with hat on
top q with hat on top over denominator n end fraction end root
First, we must determine the corresponding z*score for 95% Confidence Interval. Remember, this means that we
have 5% for the tails, meaning 5%, or 0.025, for each tail. Using a z-table, we can find the upper z-score by
finding (1 - 0.025) or 0.975 in the table.
This corresponding z-score is at 1.96.
We can know p with hat on top comma space q with hat on top comma space a n d space n.
So putting it all together:
