Can someone help me out with this

A professor claims that his students' average score on the first exam of the semester is different than the average score on the

Marta_Voda [28]

Answer:

$t=\frac{\bar d -0}{\frac{s_d}{\sqrt{n}}}=0.704$

$p_v = 2*P(t_{7} >0.704)=0.504$

So the p value is higher the significance level given 0.1, so then we can conclude that we FAIL to reject the null hypothesis that the difference mean between after and before score is equal 0. So then we don't have enough evidence to say that the score for the second exam is different than the score for the first exam.

Step-by-step explanation:

Previous concepts

A paired t-test is used to compare two population means where you have two samples in which observations in one sample can be paired with observations in the other sample. For example if we have Before-and-after observations (This problem) we can use it.

Let put some notation

x=test value before (first exam) , y = test value after (second exam)

The system of hypothesis for this case are:

Null hypothesis: $\mu_y -\mu_x =0$

Alternative hypothesis: $\mu_y -\mu_x \neq 0$

The first step is calculate the difference $d_i=y_i-x_i$

The statistic given by :

$t=\frac{\bar d -0}{\frac{s_d}{\sqrt{n}}}=0.704$

The next step is calculate the degrees of freedom given by:

$df=n-1=8-1=7$

Now we can calculate the p value, since we have a left tailed test the p value is given by:

$p_v = 2*P(t_{7} >0.704)=0.504$

So the p value is higher the significance level given 0.1, so then we can conclude that we FAIL to reject the null hypothesis that the difference mean between after and before score is equal 0. So then we don't have enough evidence to say that the score for the second exam is different than the score for the first exam.

5 0

3 years ago

Classify the polynomial by degree and number of terms.<br> 2+3x^3-7x^3+10

larisa86 [58]

Answer:

−4x^3+12

Step-by-step explanation:

2+3x^3-7x^3+10

simplify this

−4x3+12

3 0

3 years ago

Given the following coordinates complete the reflection transformation.

Karolina [17]

Answer:

For a general point (x, y), a reflection across the line x = a transforms the point into:

(a + (a - x), y) = (2a - x, y)

So if we first do a reflection across the line x = 1, the new point will be:

(2*1 - x, y) = (2 - x, y)

And if we now do a reflection across the line x = 3, the new point will be:

(2*3 - (2 - x), y) = (6 - 2 + x, y) = (4 + x, y)

Now that we have the general formula we can solve the question.

For the point (-5, 2)

The generated point after the reflections is:

(4 + (-5), 2) = (-1, 2)

For the point (-1, 5)

The generated point after the reflections is:

(4 + (-1), 5) = (3, 5)

For the point (0, 3)

The generated point after the reflections is:

(4 +0, 3) = (4, 3)

8 0

3 years ago

Hey, what is 2000x5?

Gnoma [55]

Answer:

Step-by-step explanation:

2000x5=10,000

3 0

3 years ago

Exhibit 13-3 To test whether or not there is a difference between treatments A, B, and C, a sample of 12 observations has been r

marta [7]

Answer:

a. 1.059

Step-by-step explanation:

Test statistics is used in hypothesis testing to find the conclusion. Test statistics are T-values which are used in testing a hypothesis and deciding whether to accept or reject the null hypothesis.

Test statistics can be calculated with the following formula:

Z = x - u / s / $\sqrt{n}$

7 0

3 years ago