Conditional probability from CDF?

$\begingroup$

Can you find a conditional probability value from a CDF? If so, how?

$F(x)=[x^2-4; 0<=x<1 [ x; 1<=x<2$

how to find $P[x>1/2 | x<2]$

$\endgroup$

1 Answer

$\begingroup$

You just have to use the definition of conditional probability, i.e.:

$$P(A|B)=\frac{P(A,B)}{P(B)}$$

so in your case:

$$P(X>\frac{1}{2}|X<2)=\frac{P(X>\frac{1}{2},X<2)}{P(X<2)}=\frac{P(\frac{1}{2}<X<2)}{P(X<2)}=\frac{F(2)-F(\frac{1}{2})}{F(2)}$$

Actually I do not really understand what is your CDF from your post, but you can compute the result now.

$\endgroup$

Your Answer

Sign up or log in

Sign up using Google Sign up using Facebook Sign up using Email and Password

Post as a guest

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

You Might Also Like