# An urn contains 5 red and 2 green balls. A ball is drawn at random from the urn. If the drawn ball is green, then a red ball is added to the urn and if the drawn ball is red, then a green ball is added to the urn; the original ball is not returned to the urn. Now, a second ball is drawn at random from it. The probability that the second ball is red, is : a. b. c. d.

## Question ID - 56751 | SaraNextGen Top Answer An urn contains 5 red and 2 green balls. A ball is drawn at random from the urn. If the drawn ball is green, then a red ball is added to the urn and if the drawn ball is red, then a green ball is added to the urn; the original ball is not returned to the urn. Now, a second ball is drawn at random from it. The probability that the second ball is red, is : a. b. c. d.

Answer Key / Explanation : (b) -

E1 : Event of drawing a Red ball and placing a green ball in the bag

E2 : Event of drawing a green ball and placing a red ball in the bag

E : Event of drawing a red ball in second draw

P(E)=P(E1) P P(E2) P

= =