Answer:
DF = 458
Step-by-step explanation:
In statistics, T-test have an extensive application. T-tests are used in hypothesis testing or inference about the population mean when the population standard deviation is not known. Nevertheless, they are used in making inference in paired samples or dependent samples t-test as well as independent samples.
The degrees of freedom, DF, is a characteristic of the student's t distribution which is used in T-tests. In a simple T-test;
DF = n - 1
where n is the sample size
Given n is 459, DF = 459 - 1 = 458
Therefore, DF = 458
I think the answer is b. cos(pi theta)= -0.6
The z score that has 70.54% of the distribution area is 9.92
<h3>What is a z-score?</h3>
The z-score is a numerical measurement used in statistics to refer to how much a given value differs from the standard deviation.
For the random variable x, the z-score is;
z = (x - 11)/2
therefore, 70.54% of the area under the curve lies to the right of x,
then the area to the left of x is;
100 - 70.54 = 29.46%
From the standard table, a z-score of -0.54 will yield an area of 29.46% to the left of x.
Therefore, we get;
(x - 11)/2 = -0.54
x - 11 = -0.54(2)
x = 9.92
The z score is 9.92
Learn more about z score here;
brainly.com/question/4167122
#SPJ1
Answer:
Around 37, first one
Step-by-step explanation:
add up all the 7th grader number, 40
125 divided by 40 is around 3.125
3.125 times 12 = 37.5
37 because there is no half a kid
Use the calculator to find the Product