Question

If a bag of marbles contains 2 blue, 2 red. 3 white and 4 yellow marbles,what is the probability that I will draw a red marble and after replacing itthen draw a yellow one?

Answer 1

The probability to draw a red marble is:

$P=\frac{2}{11}$

Because there are 11 marbles in the bag and 2 of them are red.

At the same way, the probability to draw a yellow marble is:

$P=\frac{4}{11}$

Because we replace the red one and there are still 11 marbles in the bag and 4 of them are yellow.

Finally, the probability that you will draw a red marble and after replacing it

then draw a yellow one is the multiplication of the probabilities calculated before, so:

$P=\frac{2}{11}\cdot\frac{4}{11}=0.0661$

Answer: 0.0661