Answer:Given:
P(A)=1/400
P(B|A)=9/10
P(B|~A)=1/10
By the law of complements,
P(~A)=1-P(A)=399/400
By the law of total probability,
P(B)=P(B|A)*P(A)+P(B|A)*P(~A)
=(9/10)*(1/400)+(1/10)*(399/400)
=51/500
Note: get used to working in fraction when doing probability.
(a) Find P(A|B):
By Baye's Theorem,
P(A|B)
=P(B|A)*P(A)/P(B)
=(9/10)*(1/400)/(51/500)
=3/136
(b) Find P(~A|~B)
We know that
P(~A)=1-P(A)=399/400
P(~B)=1-P(B)=133/136
P(A∩B)
=P(B|A)*P(A) [def. of cond. prob.]
=9/10*(1/400)
=9/4000
P(A∪B)
=P(A)+P(B)-P(A∩B)
=1/400+51/500-9/4000
=409/4000
P(~A|~B)
=P(~A∩~B)/P(~B)
=P(~A∪B)/P(~B)
=(1-P(A∪B)/(1-P(B)) [ law of complements ]
=(3591/4000) ÷ (449/500)
=3591/3592
The results can be easily verified using a contingency table for a random sample of 4000 persons (assuming outcomes correspond exactly to probability):
===....B...~B...TOT
..A . 9 . . 1 . . 10
.~A .399 .3591 . 3990
Tot .408 .3592 . 4000
So P(A|B)=9/408=3/136
P(~A|~B)=3591/3592
As before.
Step-by-step explanation: its were the answer is
All you do is divide -12/20 by 4/4 which is -3/5
Answer:
is it 4.8, I don't really know
Answer: I think y is 32 im not good at this tho
Step-by-step explanation:
Answer:
y=3/4x-2.5
Step-by-step explanation:
This is a straight line, so it would follow the equation y=mx+b. You can find the b value by looking at the y-intercept of the equation (where x=0), which in this case would be -2.5. Then, you can find the m value by comparing the two given points' locations. Slope is rise over run, so first you can find the rise. The y value moves from y=-4 to y=2, which is a value of 6 units upward. The points move from x=-2 to x=6, which is a distance of 8 units. Finally, put it into the rise over run pattern, giving you 6/8, which simplified is 3/4. This is your m value. Finally, plug in your two variable values into y=mx+b and you'll get y=3/4x-2.5.
