Question 1:

What does it mean when the values in the column of differences (without - with) are negative?

Question 2:

You wish to test the following claim (HAHA) at a significance level of =0.10. For the context of this problem, d=newold where the first data set represents the hours of stand-by battery life for an old smartphone and the second data set represents the hours of stand-by battery life of a new model of the smartphone. Ho:d=0 Ha:d0 You believe the population of difference scores is normally distributed, but you do not know the standard deviation. You obtain the following sample of data (hours of stand-by time):

old model	new model
68.4	26.5
59.4	38.2
50.2	25.1
54.3	22.9
62.7	73.8
57.9	90.7
46.3	40.6
62.4	65.9

What is the test statistic for this sample? (Report answer accurate to three decimal places.) t=____ The p-value is ____ This p-value leads to a decision to...

• reject the null
• accept the null
• fail to reject the null

As such, the final conclusion is that...

• There is sufficient evidence in the sample data to support the claim that on average, the new battery life and old batteyr life for the product are different..
• There is not sufficient evidence in the sample data to support the claim that on average, the new battery life and old batteyr life for the product are different.

Question 3:

You wish to test the following claim (Ha) at a significance level of =0.01. For the context of this problem, d=PostTestPreTest where the first data set represents a pre-test and the second data set represents a post-test. (Each row represents the pre and post test scores for an individual. Be careful when you enter your data and specify what your 1 and 2 are so that the differences are computed correctly.) Ho:d=0 Ha:d0 You believe the population of difference scores is normally distributed, but you do not know the standard deviation. You obtain the following sample of data:

pre-test	post-test
26.8	1.2
44.9	46.4
66.3	70.4
59.9	77.5
37.2	46.2
59.9	54.7
47.2	19.3
26.1	30.6
42.2	48.6
8.1	-7.3
55.1	60.1
44.5	44.8

What is the test statistic for this sample? test statistic = _____ (Report answer accurate to 4 decimal places.) What is the p-value for this sample? p-value = ______ (Report answer accurate to 4 decimal places.) The p-value is...

• less than (or equal to)
• greater than

This test statistic leads to a decision to...

• reject the null
• accept the null
• fail to reject the null

As such, the final conclusion is that...

• There is sufficient evidence to warrant rejection of the claim that the mean difference of post-test from pre-test is not equal to 0.
• There is not sufficient evidence to warrant rejection of the claim that the mean difference of post-test from pre-test is not equal to 0.
• The sample data support the claim that the mean difference of post-test from pre-test is not equal to 0.
• There is not sufficient sample evidence to support the claim that the mean difference of post-test from pre-test is not equal to 0.