JEE Math Practice Question
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.$${{21} \over {49}}$$
- B.$${{27} \over {49}}$$
- C.$${{26} \over {49}}$$
- D.$${{32} \over {49}}$$
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