Evaluate [tex]\( t = \frac{\overline{d} - \mu_{d}}{\frac{s_d}{\sqrt{n}}} \)[/tex] for [tex]\( \overline{d} = -0.625, \mu_{d} = 0, s_d = 2.669 \)[/tex], and [tex]\( n = 8 \)[/tex].

[tex]\( t = \square \)[/tex] (Round to three decimal places as needed.)



Answer :

Sure, let's go through the problem step by step.

To evaluate the t-statistic using the formula:
[tex]\[ t = \frac{\overline{d} - \mu_d}{\frac{s_d}{\sqrt{n}}} \][/tex]

we need to plug in the given values:
- [tex]\(\overline{d} = -0.625\)[/tex]
- [tex]\(\mu_d = 0\)[/tex]
- [tex]\(s_d = 2.669\)[/tex]
- [tex]\(n = 8\)[/tex]

First, calculate the denominator, which is [tex]\(\frac{s_d}{\sqrt{n}}\)[/tex].

1. Compute the square root of [tex]\(n\)[/tex]:
[tex]\[ \sqrt{n} = \sqrt{8} \approx 2.828 \][/tex]

2. Divide [tex]\(s_d\)[/tex] by [tex]\(\sqrt{n}\)[/tex]:
[tex]\[ \frac{s_d}{\sqrt{n}} = \frac{2.669}{2.828} \approx 0.943 \][/tex]

Now, calculate the numerator:
[tex]\[ \overline{d} - \mu_d = -0.625 - 0 = -0.625 \][/tex]

Next, divide the numerator by the denominator:
[tex]\[ t = \frac{\overline{d} - \mu_d}{\frac{s_d}{\sqrt{n}}} = \frac{-0.625}{0.943} \approx -0.662 \][/tex]

Thus, the value of [tex]\(t\)[/tex] rounded to three decimal places is:
[tex]\[ t \approx -0.662 \][/tex]