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.
2.903

Question 13 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.
The ABC battery company claims that their batteries last at least 100 hours, on average. Your experience
with their batteries has been somewhat different, so you decide to conduct a test to see if the company's
claim is true. You believe that the mean life is actually less than 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
:
100
Sample mean 98.5
Std error of mean 0.777
Assuming the life length of batteries is normally distributed, what is the p-value associated with this test?
Place your answer, rounded to 3 decimal places in the blank. For example, 0.234 would be a legitimate
entry.
.034

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.
A firm that produces light bulbs claims that their lightbulbs last 1500 hours, on average. You wonder if the
average might differ from the 1500 hours that the firm claims. To explore this possibility you take a
random sample of n = 25 light bulbs purchased from this firm and record the lifetime (in hours) of each
bulb. You then conduct an appopriate test of hypothesis. Some of the information related to the
hypothesis test is presented below.
Test of H
0
:
= 1500 versus H
1
:
1500