Answer:
Option C is correct.
Step-by-step explanation:
-x+3y=2
4x-2y=22
In matrix form is represented as:
![\left[\begin{array}{cc}-1&3\\4&-2\end{array}\right] \left[\begin{array}{c}x&y\end{array}\right] =\left[\begin{array}{c}2&22\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-1%263%5C%5C4%26-2%5Cend%7Barray%7D%5Cright%5D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7Dx%26y%5Cend%7Barray%7D%5Cright%5D%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D2%2622%5Cend%7Barray%7D%5Cright%5D)
AX=B
|A| = (-1)(-2)-(3)(4)
|A| = 2-12
|A| = -10
Adj A = ![\left[\begin{array}{cc}-2&-3\\-4&-1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-2%26-3%5C%5C-4%26-1%5Cend%7Barray%7D%5Cright%5D)
A^-1 = -1/10
A^-1 = 1/10![\left[\begin{array}{cc}2&3\\4&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D2%263%5C%5C4%261%5Cend%7Barray%7D%5Cright%5D)
X= A^-1 B
X = 1/10![\left[\begin{array}{c}2&22\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D2%2622%5Cend%7Barray%7D%5Cright%5D)
X=1/10![X=1/10\left[\begin{array}{c}2*2+3*22\\4*2+1*22\end{array}\right]\\X=1/10\left[\begin{array}{c}4+66\\8+22\end{array}\right]\\X=1/10\left[\begin{array}{c}70\\30\end{array}\right]\\X=\left[\begin{array}{c}70/10\\30/10\end{array}\right]\\X=\left[\begin{array}{c}7\\3\end{array}\right]](https://tex.z-dn.net/?f=X%3D1%2F10%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D2%2A2%2B3%2A22%5C%5C4%2A2%2B1%2A22%5Cend%7Barray%7D%5Cright%5D%5C%5CX%3D1%2F10%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D4%2B66%5C%5C8%2B22%5Cend%7Barray%7D%5Cright%5D%5C%5CX%3D1%2F10%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D70%5C%5C30%5Cend%7Barray%7D%5Cright%5D%5C%5CX%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D70%2F10%5C%5C30%2F10%5Cend%7Barray%7D%5Cright%5D%5C%5CX%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D7%5C%5C3%5Cend%7Barray%7D%5Cright%5D)
So, x = 7 and y =3
Hence Option C is correct.
Answer:
The answer is 455.
Step-by-step explanation:
You add them all up, then divide the sum by 3.
Answer:
A. The 99% confidence interval for the difference in the proportion of all dinner customers and all lunch customers who are served within 2 minutes is between -0.195 and 0.289. (0.714 - 0.667) ± 2.576*(√0.714(1- 0.714)/35 + 0.667(1- 0.667)/75).
B. Since the confidence interval contains 0, we cannot conclude that the proportion of customers served within 2 minutes of placing their order is greater during lunch hours than during dinner hours.
Step-by-step explanation:
got this off chegg.
