probability of selecting a red ball and then a white ball on 2 successive draws if the ball is returned to the bag after the first draw:
P(red) * P(white)
(3/9) * (2/9) = 6/81 or 2/27
answer choice A.
Oh yeah... That's exactly why I posted this
Your Answer : A
Actual Answer : D
Probability of a desired outcome = Number of favourable outcomes / Total number of possible outcomes.
There are a total of 9 balls in the bag.
3 out of the total 9 balls are red.
Probability of drawing a red ball = 3/9
The one ball that is drawn is returned back into the bag and another ball is drawn.
Now, 2 out of the total 9 balls are white.
Probability of drawing a white ball = 2/9.
Hence probability of drawing a red and a white ball in two successive draws = 3/9 * 2/9 = 1/3 * 2/9 = 2/27.
The order in which the ball is drawn is not specified. It could be a red ball first or it could be a white ball first.
Hence the probability will be 2/27 + 2/27 = 4/27.
Hence (D) is the correct answer.