Answer:
Given:
Null hypothesis: the average salary for new college graduates with a job is $50,556.
Alternative hypothesis: the graduates from a university earn more than that average.
Using the z-test:
=> Calculate the value of test statistic:
t = (mean of sample - mean of null hypothesis)/(std/sqrt(number of sample)
= (53200 - 50556)/(10200/sqrt(100))
= 2.592 > 1.645
=> Reject the null hypothesis, their graduates earn more than average
Hope this helps!
:)
We found a counterexample, so the statement is false.
<h3>
Is the statement true?</h3>
Let's use the matrix:
![\left[\begin{array}{cccc}-2&0&0&0\\0&1&0&0\\0&0&1&0\\ 0&0&0&1 \end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D-2%260%260%260%5C%5C0%261%260%260%5C%5C0%260%261%260%5C%5C%200%260%260%261%20%5Cend%7Barray%7D%5Cright%5D)
This is a 4x4 matrix with determinant equal to -2.
The inverse matrix is:
![\left[\begin{array}{cccc}1/2&0&0&0\\0&-1&0&0\\0&0&-1&0\\ 0&0&0&-1 \end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%2F2%260%260%260%5C%5C0%26-1%260%260%5C%5C0%260%26-1%260%5C%5C%200%260%260%26-1%20%5Cend%7Barray%7D%5Cright%5D)
If we multiply it by 2, we get:
![\left[\begin{array}{cccc}1&0&0&0\\0&-2&0&0\\0&0&-2&0\\ 0&0&0&-2 \end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%260%260%260%5C%5C0%26-2%260%260%5C%5C0%260%26-2%260%5C%5C%200%260%260%26-2%20%5Cend%7Barray%7D%5Cright%5D)
The adjoint of that is the original matrix, actually:
Which we already know, has a determinant of -2.
So the statement is false, as we found a counterexample.
If you want to learn more about matrices:
brainly.com/question/11989522
#SPJ1
Answer: 0.98 cents
Step-by-step explanation:
First you want to get the amount of apples to one pound.
3.5 to 1
3.5 divided by 3.5 equals to one.
Now you need to o the same thing to the cost
3.43 divided by 3.5
= 0.98
since we are talking money it would be 0.98 cents
