Answer:
0.8594
Step-by-step explanation:
Let a denote the event of forgetting to shut off machine and b be the event of being defective.
-A foreman forgets to shut off machine 55% of the time.
-If he forgets, 15% of molds are defective.
-If he does not, 3% of molds are defective.
#The probability that he forgot to shut off the machine is calculated as:
![P(a \ and \ b)=0.55\times 0.15\\\\=0.0825\\\\](https://tex.z-dn.net/?f=P%28a%20%5C%20and%20%5C%20b%29%3D0.55%5Ctimes%200.15%5C%5C%5C%5C%3D0.0825%5C%5C%5C%5C)
P(a and ~b)=0.55(1-0.15)=0.4675
P(~a and b) = (1-0.55)*0.03=0.0135
P(~a and ~b) = (1-0.55)*(1-0.03)=0.4365
#Conditional probability is defined as:
![P(a|b)=\frac{P(a \ and\ b)}{P(a)}\\\\=\frac{P(a \ and \ b)}{[(P(a \ and \ b)+P(\~a \ and \ b)}\\\\\\=\frac{0.0825}{0.0825+0.0135}\\\\\\=0.8594](https://tex.z-dn.net/?f=P%28a%7Cb%29%3D%5Cfrac%7BP%28a%20%5C%20and%5C%20%20b%29%7D%7BP%28a%29%7D%5C%5C%5C%5C%3D%5Cfrac%7BP%28a%20%5C%20and%20%5C%20b%29%7D%7B%5B%28P%28a%20%5C%20and%20%5C%20b%29%2BP%28%5C~a%20%5C%20and%20%5C%20b%29%7D%5C%5C%5C%5C%5C%5C%3D%5Cfrac%7B0.0825%7D%7B0.0825%2B0.0135%7D%5C%5C%5C%5C%5C%5C%3D0.8594)
Hence, the probability that the foreman forgot to shut off the machine the previous night is 0.8594
So if we want to know the common solution(s) to a system of 2 equations, So we can just set both equations equal to each other and solve for the x value(s). That’s where I start below;
2x^2-13x+21 = 2x^2+9x-56
2x^2 cancels out and moving everything to one side and anything with an x variable to the other side we have then;
-22x=-77
22x=77 by cancelling the negative signs
x=77/22 therefore x=7/2 or 3.5
Hope this helps you. Any questions please ask.
Answer:
28
Step-by-step explanation: