A fair coin is tossed 5 times. What is the probability of obtaining exactly 2 heads if it is known that at least 1 head appeared?
Last edited by mr fantastic; Nov 13th 2011 at 10:47 AM. Reason: Re-titled.
Follow Math Help Forum on Facebook and Google+
What is the probability of exactly one (1) "heads" in four tosses? Are you sure it's trickier than that? If so, why?
what do you mean?
Originally Posted by mtingt A fair coin is tossed 5 times. What is the probability of obtaining exactly 2 heads if it is known that at least 1 head appeared? Let X be the random variable 'Number of heads'. Calculate $\displaystyle Pr(X = 2 | X \geq 1)$ using the usual formula for conditional probability.
View Tag Cloud