contestada

At Rachel’s 11th birthday party, eight girls were timed to see how long (in seconds) they could hold their breath in a relaxed position. After a two-minute rest, they timed themselves while jumping. The girls thought that the mean difference between their jumping and relaxed times would be zero. Test their hypothesis.At Rachel’s 11th birthday party, eight girls were timed to see how long (in seconds) they could hold their breath in a relaxed position. After a two-minute rest, they timed themselves while jumping.
Relaxed time (seconds)
Jumping time (seconds)
26
21
47
40
30
28
22
21
23
25
45
43
37
35
29
32

Respuesta :

Answer: Since p-value is greater than α = 0.05, we cannot reject the hypothesis H0, and we can conclude that it is insufficient evidence to conclude that the average difference is not zero.

Step-by-step explanation:

Step 1: We need to test the given hypothesis.

Step 2: Explanation

We can take x1- x2 to represent the difference between the jumping and relaxed times.

[tex]H0: u1 = u2\\H1: u1 \neq u2[/tex]

Step 3: Simplification

We need to find the mean and standard deviation of both samples.

[tex]u1 = 32.375, s1 = 9.620477\\u2 = 30.625, s2 = 8.331309[/tex]

The differences between the jumping and relaxed times are calculated:

[tex]5, 7, 2, 1, -2, 2, 2, -3[/tex]

The number of differences is ∑(8, i-1) = [tex](d_{i} - \alpha ) ^{2}[/tex] = 75.5

Standard deviation differences are:

[tex]\sqrt{\frac{75.5}{7} }[/tex] = 3.284

The standard error is SE = 1.161

Using this, we can find the value of the test statistic t:

[tex]t = \frac{u1 - u2}{SE}[/tex] = 1.507

Using this and the graph, we get that the p value is 0.17554.

Therefore, since p-value is greater than α = 0.05, we cannot reject the hypothesis H0, and we can conclude that it is insufficient evidence to conclude that the average difference is not zero.

Otras preguntas