Need help on stats homework

Xylitol

Diamond Member
Aug 28, 2005
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An event A will occur with probability 0.5. An event B will occur with probability 0.6. The probability that both A and B will occur is 0.1. Find the conditional probability of A given B

a. 0.5 b. 0.3 c. 0.2 d. 1/6
e. cannot be determined from the information given


The answer is D (1/6)




I thought that these events were independent, so P(A|B) = P(A)
Maybe they're not independent?

Help
Thanks


edit: got it
 

Leros

Lifer
Jul 11, 2004
21,867
7
81
If it was independent then
P(A & B) = P(A)*P(B)

0.1 =/= 0.5 *0.6

So they are dependent.

 

Leros

Lifer
Jul 11, 2004
21,867
7
81
P(A|B) = P(A & B) / P(B)

I'm actually using this formula right now, albeit in a more complicated usage.