If-two-events-A-and-B-are-such-that-P-A-c-0-3-P-B-0-4-and-P-A-B-c-0-5-then-P-B-A-B-c-A-0-20-B-0-25-C-0-30-D-0-35-

Question Number 182695 by cortano1 last updated on 13/Dec/22

If two events A and B are such

that P (A^{c}) = 0.3; P (B) = 0.4 and

P (A \cap B^{c}) = 0.5 then P (\frac{B}{A \cup B^{c}}) = ?

(A) 0.20 (B) 0.25 (C) 0.30 (D) 0.35

Commented by Acem last updated on 13/Dec/22

H i f r i e n d!

W h a t d o e s A^{c} m e a n ?

Commented by Emrice last updated on 13/Dec/22

it is the conditional probability. and in our case here it is the probability of A knowing C.

Answered by greougoury555 last updated on 14/Dec/22

P (B / A \cup \overset{―}{B}) = \frac{P (A \cap B)}{P (A \cup \overset{―}{B})}

= \frac{0.7 - 0.5}{0.7 + 0.6 - 0.5} = \frac{0.2}{0.8} = 0.25