STATISTICS MISC Statistics Unit 5 Milestone Course Hero.
STATISTICS MISC Statistics Unit 5 Milestone Course Hero.
Score 19/24
You passed this Milestone
19 questions were answered correctly.
Joe is measuring the widths of doors he bought to install in an apartment complex. He measured 72 doors and
found a mean width of 36.1 inches with a standard deviation of 0.3 inches. To test if the doors differ significantly
from the standard industry width of 36 inches, he computes a z-statistic.
What is the value of Joe's z-test statistic?
2.83
-1.81
-2.83
1.81
1/22
,STATISTICS MISC Statistics Unit 5 Milestone Course Hero.
RATIONALE
2/22
, STATISTICS MISC Statistics Unit 5 Milestone Course Hero.
If we first note the denominator of
Then, getting the z-score we can note it is
This tells us that 36.1 is 2.83 standard deviations above the value of 36.
Note that when you round some values you may get slightly different results, but the results should be relatively
close to this final calculated value.
CONCEPT
Z-Test for Population Means
2
Emile has calculated a one-tailed z-statistic of -1.97 and wants to see if it is significant at the 5% significance
level.
What is the critical value for the 5% significance level? Answer choices are rounded to the hundredths
place.
-2.33
0
-1.04
-1.64
RATIONALE
Recall that when a test statistic is smaller than in a left-tailed
test we would reject Ho. The closest value to 5%, or 0.05, in the table would be between 0.0505 and 0.495.
0.0505 corresponds with a z-score of -1.64
0.0495 corresponds with a z-score of -1.65.
We need to calculate the average of the two z-scores to get a z-score of -1.645.
CONCEPT
How to Find a Critical Z Value
3
3/22
STATISTICS MISC Statistics Unit 5 Milestone Course Hero.
Score 19/24
You passed this Milestone
19 questions were answered correctly.
Joe is measuring the widths of doors he bought to install in an apartment complex. He measured 72 doors and
found a mean width of 36.1 inches with a standard deviation of 0.3 inches. To test if the doors differ significantly
from the standard industry width of 36 inches, he computes a z-statistic.
What is the value of Joe's z-test statistic?
2.83
-1.81
-2.83
1.81
1/22
,STATISTICS MISC Statistics Unit 5 Milestone Course Hero.
RATIONALE
2/22
, STATISTICS MISC Statistics Unit 5 Milestone Course Hero.
If we first note the denominator of
Then, getting the z-score we can note it is
This tells us that 36.1 is 2.83 standard deviations above the value of 36.
Note that when you round some values you may get slightly different results, but the results should be relatively
close to this final calculated value.
CONCEPT
Z-Test for Population Means
2
Emile has calculated a one-tailed z-statistic of -1.97 and wants to see if it is significant at the 5% significance
level.
What is the critical value for the 5% significance level? Answer choices are rounded to the hundredths
place.
-2.33
0
-1.04
-1.64
RATIONALE
Recall that when a test statistic is smaller than in a left-tailed
test we would reject Ho. The closest value to 5%, or 0.05, in the table would be between 0.0505 and 0.495.
0.0505 corresponds with a z-score of -1.64
0.0495 corresponds with a z-score of -1.65.
We need to calculate the average of the two z-scores to get a z-score of -1.645.
CONCEPT
How to Find a Critical Z Value
3
3/22
