Answer:
im almost postive the one you marked is correct
Step-by-step explanation:
The tree diagram of the problem above is attached
There are four outcomes of the two events,
First test - Cancer, Second Test - Cancer, the probability is 0.0396
First test - Cancer, Second Test - No Cancer, the probability is 0.0004
First test - No Cancer, Second Test - There is cancer, the probability is 0.0096
First test - No cancer, Second Test - No cancer, the probability is 0.9054
The probability of someone picked at random has cancer given that test result indicates cancer is

The probability of someone picked at random has cancer given that test result indicates no cancer is
Answer:
x=1 y = -1/2
(1,-1/2)
Step-by-step explanation:
7x-2y=8
5x+2y=4
I would use elimination since we have 2y in one equation and -2y in the other
7x-2y=8
5x+2y=4
--------------------
12x = 12
Divide each side by 12
12x/12 = 12/12
x =1
The substitute back into equation 2
5(1) +2y = 4
5 +2y = 4
Subtract 5
5-5+2y = 4-5
2y = -1
Divide by 2
2y/2 = -1/2
y = -1/2
It is 16 because 3x16=48 and 4x16=64!