There are 3 red and 8 green balls in a bag. If you randomly choose balls one at a time, with replacement, what is the probability of choosing 2 red balls and then 1 green ball?
The fact that the ball is replaced each time, means that the probabilities stay the same each time a ball is chosen.
P(red, red, green) = P(red) x P(red) x P(green)
:. Reqd. Prob.
There are 3 Red + 8 Green = 11 balls in the bag, out of which, 1 ball can be chosen in 11 ways. This is total no. of outcomes.
Out of 3 Red balls, 1 Red ball can be chosen in 3 ways. This is no. of outcomes favourable to
This is the Conditional Prob. of occurrence of
, knowing that
Finally, on the same line of arguments, we have,
Hope, this will be helpful! Enjoy Maths.!