-41 would be the solution.
Answer:
The probability is 0.04746
Step-by-step explanation:
Firstly, we calculate the z-score here
Mathematically;
z-score = x-mean/SD/√n
Where from the question;
x = 85, mean = 90 , SD = 15 and n = 25
Plugging these values into the equation, we have;
Z = (85-90)/15/√25 = -5/15/5 = -1.67
So the probability we want to calculate is ;
P(z > -1.67)
We use the standard normal distribution table for this;
P(z > -1.67) = 0.04746
Answer:
The cost of an oil change for 1 truck was $42
Step-by-step explanation:
Let
x -----> the cost of an oil change for 1 truck
y -----> the cost of gas for 1 truck
z ----> the total bill
we know that
![z=11[x+y]](https://tex.z-dn.net/?f=z%3D11%5Bx%2By%5D)
we have
substitute and solve for x
![694.32=11[x+21.12]](https://tex.z-dn.net/?f=694.32%3D11%5Bx%2B21.12%5D)
C, the answer is C.. trust me
Answer:
<em>(1, - 2) </em>
Step-by-step explanation:
2x - y = 4
3x + y = 1
A = ![\left[\begin{array}{cc}2&-1\\3&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D2%26-1%5C%5C3%261%5Cend%7Barray%7D%5Cright%5D)
= 2(1) - 3( - 1) =2 + 3 = 5
= ![\left[\begin{array}{cc}4&-1\\1&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D4%26-1%5C%5C1%261%5Cend%7Barray%7D%5Cright%5D)
= 4(1) - 1(- 1) = 4 + 1 = 5
= ![\left[\begin{array}{cc}2&4\\3&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D2%264%5C%5C3%261%5Cend%7Barray%7D%5Cright%5D)
= 2(1) - 4(3) = 2 - 12 = - 10
<em>x </em>= 
=<em> 1</em>
<em>y </em>= 
= <em>- 2</em>
<em>(1, - 2)</em>
