Answer:
The 90% confidence interval for the mean test score is between 77.29 and 85.71.
Step-by-step explanation:
We have the standard deviation for the sample, so we use the t-distribution to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 25 - 1 = 24
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 24 degrees of freedom(y-axis) and a confidence level of
. So we have T = 2.064
The margin of error is:

In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 81.5 - 4.21 = 77.29
The upper end of the interval is the sample mean added to M. So it is 81.5 + 4.21 = 85.71.
The 90% confidence interval for the mean test score is between 77.29 and 85.71.
Answer:
times -6
Explanation... 2 x 10-6 x -6=56
6 x 10-4=56
Hope this helps
-2x*(-3x)-2x*(-4y)-2x*(-8)
answer :6x^2+8xy+16x
Most earthquakes occur along the edge of the oceanic and continental plates. So, when they slide past each other. Many think it's when they pull apart but that has mixed results.
The number of edges of a polyhedron with 4 faces and 4 vertices will be 6.
<h3>What is a polygon?</h3>
The polygon is a 2D geometry that has a finite number of sides. And all the sides of the polygon are straight lines connected to each other side by side.
Using Euler's formula, the number of the edges does a polyhedron with 4 faces and 4 vertices have
We know the formula for the edges of the polyhedron will be
F + V = E + 2
The number of faces, vertices, and edges of a polyhedron are denoted by the letters F, V, and E.
Then we have
4 + 4 = E + 2
E = 8 - 2
E = 6
More about the polygon link is given below.
brainly.com/question/17756657
#SPJ1