Solve Probability Problem: Find P(B) & P(A/B)

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chwala
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Homework Statement

## The question is as follows given ##P(A/B)=0.8, P(B/A")=0.6## and P(A)=0.75 then find P(B) and ## P(A/B)##[/B]

Homework Equations

The Attempt at a Solution


##P(A/B)= P(AnB)/P(B) ## where## P(AnB)= P(B/A).P(A)= 0.8*0.75=0.6##
##P(A/B)= 0.6/P(B)## am now stuck here how do i move from here?
 
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chwala said:

Homework Statement

[/B]
Given ##P(A/B)=0.8, P(B/A')=0.6## and ##P(A)=0.75## then find ##P(B)## and ## P(A/B)##

Homework Equations

The Attempt at a Solution


##P(A/B)= P(A\land B)/P(B) ## where ## P(A\land B)= P(B/A)P(A)= 0.8*0.75=0.6##
##P(A/B)= 0.6/P(B)## am now stuck here how do i move from here?

looks like you're nearly there... calculate ## p(A') ##, then can you find ## p(A' \land B)## ?
 
If you are given [itex]P(A \mid B)[/itex] why do you need to calculate it?

To be clear: are these the items you are given and the items you are to find?
[tex] \begin{align*}<br /> P(A \mid B) & = 0.8 \\<br /> P(B \mid A') & = 0.6 \\<br /> P(A) & = 0.75 \\<br /> \text{Need} & \\<br /> P(B) & \\<br /> P(A \cap B) \text{ (instead of } & P(A \mid B) \text{?)}<br /> \end{align*}[/tex]
 
statdad said:
If you are given [itex]P(A \mid B)[/itex] why do you need to calculate it?

To be clear: are these the items you are given and the items you are to find?
[tex] \begin{align*}<br /> P(A \mid B) & = 0.8 \\<br /> P(B \mid A') & = 0.6 \\<br /> P(A) & = 0.75 \\<br /> \text{Need} & \\<br /> P(B) & \\<br /> P(A \cap B) \text{ (instead of } & P(A \mid B) \text{?)}<br /> \end{align*}[/tex]
sorry the terms given are P(B/A)= 0.8 , P(B/A")=0.6 and P(A)=0.75 I need to find P(A/B) and P(B)
 
Well, if you have [itex]P(B \mid A)[/itex] and [itex]P(A)[/itex] you can calculate [itex]P(A \cap B)[/itex] . You can also find [itex]P(A')[/itex] and
then get [itex]P(A' \cap B)[/itex]. What will [itex]P(A \cap B)[/itex] and [itex]P(A' \cap B)[/itex] together get you? Once you have that you can finish the questions.