SOLUTION: Given P(A)=0.2; P(B) = 0.5, P(A|B) = 0.3: (a) Compute P(A and B). (b) Compute P(A or B). P(A) = 0.2; P(B) = 0.5; PA\B) = 0.3; Compute P(A and B) Note = P(A) = 1 P(A)

Algebra ->  Probability-and-statistics -> SOLUTION: Given P(A)=0.2; P(B) = 0.5, P(A|B) = 0.3: (a) Compute P(A and B). (b) Compute P(A or B). P(A) = 0.2; P(B) = 0.5; PA\B) = 0.3; Compute P(A and B) Note = P(A) = 1 P(A)       Log On


   

Question 577857: Given P(A)=0.2; P(B) = 0.5, P(A|B) = 0.3:
(a) Compute P(A and B).
(b) Compute P(A or B).
P(A) = 0.2; P(B) = 0.5; PA\B) = 0.3;
Compute P(A and B)
Note = P(A) = 1 P(A)
0.2 =1 P(A)
.2 = 1.0 P(A)
Please help me with this problem. So I can understand what I am doing.
Thanks
Found 2 solutions by jim_thompson5910, spunky:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
I'll do the first one to get you started.

a)

P(A|B) = P(A and B)/P(B)

0.3 = P(A and B)/0.5

0.15 = P(A and B)

P(A and B) = 0.15

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b)
I'll let you try this one. Use the formula

P(A or B) = P(A) + P(B) - P(A and B)

to find the answer.


Answer by spunky(1) About Me  (Show Source):
You can put this solution on YOUR website!

P(A) = 0.2, P(B) = 0.5, P(A\B) = 0.3:
P(A\B) = P(A and B) P(B)
0.3 = P(A and B) 0.5
0.15 P(A and B)
P(A and B) = 0.15

B. P(A or B) = P(A) + P(B) - P(A and B)
0.2 + 0.5 - 0.15
0.70 - 0.15 = 0.55