3
$\begingroup$

You are dealt five cards from 52 card deck that is thoroughly shuffled. What is the probability that two out of five cards are seven?

Is it: $${4C2 . 12C3 . (4C1)^3} / 52C5$$

$\endgroup$
6
$\begingroup$

Kindly consult the Wikipedia page on Hypergeometric distribution. The correct formula is $$\frac{\binom{4}{2}\binom{48}{3}}{\binom{52}{5}}.$$ So $\binom{12}{3} \binom{4}{1}^3$ is incorrect.

$\endgroup$

Your Answer

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

Not the answer you're looking for? Browse other questions tagged or ask your own question.