Question 14 of 20
1.0/ 1.0 Points
Accepted characters
: numbers, decimal point markers (period or comma), sign indicators (-),
spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation).
NOTE:
For
scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated
values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
At a university, the average cost of books per student has been $600 per student per semester.
The Dean of Students believes that the costs are increasing and that the average is now greater
than $600. He surveys a sample of 40 students and finds that for the most recent semester their
average cost was $645 with a standard deviation of $75. What is the test value for this
hypothesis test?

Test value:
3.79
Round your answer to two decimal places as necessary.

Question 15 of 20
0.0/ 1.0 Points
Accepted characters
: numbers, decimal point markers (period or comma), sign indicators (-),
spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation).
NOTE:
For
scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated
values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
The ABC battery company claims that their batteries last 100 hours, on average. You decide to
conduct a test to see if the company's claim is true. You believe that the mean life may be
different from the 100 hours the company claims. You decide to collect data on the average
battery life (in hours) of a random sample of n = 20 batteries. Some of the information related to
the hypothesis test is presented below.
Test of H
0
:
= 100 versus H
1
:
Sample mean 98.5
Std error of mean 0.777
Assuming the life length of batteries is normally distributed, if you wish to conduct this test at
the 0.05 level of significance, what are the critical values that you should use? Place the smaller
critical value, rounded to 3 decimal places, in the first blank. For example, -1.234 would be a
legitimate entry. -2.093 . Place the larger critical value, rounded to 3 decimal places, in the
second blank. For example, 1.234 would be a legitimate entry. 2.093
100

Question 16 of 20
0.0/ 1.0 Points
Accepted characters
: numbers, decimal point markers (period or comma), sign indicators (-),
spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation).
NOTE:
For
scientific notation, a period MUST be used as the decimal point marker.