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 :

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b. |
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c. |
d. |

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. |

1 Answer

127 votes

E_{1} : Event of drawing a Red ball and placing a green ball in the bag

E_{2} : 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(E_{1}) P P(E_{2}) P

= =

127 votes

127