Answer:
84%
Step-by-step explanation:
The empirical rule states that 68% values are within 1 standard deviation of mean, i.e,
70
±
15
or from 55 to 85. Since normal distribution is symmetric, we must have (32%) outside this range, and 32/2=16% on the right if this range. Hence below 85 we have (100-16) % = 84%
Answer:
The probability that a randomly selected high school senior's score on mathematics part of SAT will be
(a) more than 675 is 0.0401
(b)between 450 and 675 is 0.6514
Step-by-step explanation:
Mean of Sat =
Standard deviation = 
We will use z score over here
What is the probability that a randomly selected high school senior's score on mathe- matics part of SAT will be
(a) more than 675?
P(X>675)

Z=1.75
P(X>675)=1-P(X<675)=1-0.9599=0.0401
b)between 450 and 675?
P(450<X<675)
At x = 675

Z=1.75
At x = 450

Z=-0.5
P(450<X<675)=0.9599-0.3085=0.6514
Hence the probability that a randomly selected high school senior's score on mathematics part of SAT will be
(a) more than 675 is 0.0401
(b)between 450 and 675 is 0.6514
Answer:
yes
Step-by-step explanation:
good job
Answer:
I think it would be finding the quantity in each group.
Step-by-step explanation:
Because there would be more than 1 group. there is only one group. so you are trying to find the number of hours each person in the group will get.
i think that is right sorry if not.
There are several ways to solve a system of equation; one of these ways is the use of matrix.
<em>Jerry made a mistake at step 2</em>
From the attachment, the step 1 is represented as:
![\mathbf{\frac 12R_1 \left[\begin{array}{cccc}1&1&1&0\\5&3&-2&-4\\3&2&1&1\end{array}\right] }](https://tex.z-dn.net/?f=%5Cmathbf%7B%5Cfrac%2012R_1%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%261%261%260%5C%5C5%263%26-2%26-4%5C%5C3%262%261%261%5Cend%7Barray%7D%5Cright%5D%20%7D)
The equation in step 2 is given as:

This means that:
We subtract the elements of row 2 from the elements of row 1, multiplied by 5
So, we have:
![\mathbf{R_2 = 5\left[\begin{array}{cccc}1&1&1&0\end{array}\right] } - \left[\begin{array}{cccc}5&3&-2&-4\end{array}\right] }](https://tex.z-dn.net/?f=%5Cmathbf%7BR_2%20%3D%205%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%261%261%260%5Cend%7Barray%7D%5Cright%5D%20%7D%20-%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D5%263%26-2%26-4%5Cend%7Barray%7D%5Cright%5D%20%7D)
Expand
![\mathbf{R_2 = \left[\begin{array}{cccc}5&5&5&0\end{array}\right] } - \left[\begin{array}{cccc}5&3&-2&-4\end{array}\right] }](https://tex.z-dn.net/?f=%5Cmathbf%7BR_2%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D5%265%265%260%5Cend%7Barray%7D%5Cright%5D%20%7D%20-%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D5%263%26-2%26-4%5Cend%7Barray%7D%5Cright%5D%20%7D)
Subtract corresponding cells
![\mathbf{R_2 = \left[\begin{array}{cccc}0&2&7&4\end{array}\right] }](https://tex.z-dn.net/?f=%5Cmathbf%7BR_2%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D0%262%267%264%5Cend%7Barray%7D%5Cright%5D%20%7D)
So, the new row 2 elements should be:
![\mathbf{ \left[\begin{array}{cccc}0&2&7&4\end{array}\right] }](https://tex.z-dn.net/?f=%5Cmathbf%7B%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D0%262%267%264%5Cend%7Barray%7D%5Cright%5D%20%7D)
However, the row 2 elements of Jerry's steps are:
![\mathbf{R_2 = \left[\begin{array}{cccc}0&-2&-7&-4\end{array}\right] }](https://tex.z-dn.net/?f=%5Cmathbf%7BR_2%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D0%26-2%26-7%26-4%5Cend%7Barray%7D%5Cright%5D%20%7D)
This means that:
Jerry made a mistake; and the mistake is at step 2
Read more about matrix at:
brainly.com/question/21848291