If two marbles are drawn at random, what is the probability

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Direction: Study the given information carefully and answer the questions that follow.
A basket contains 4 red, 5 blue and 3 green marbles.

If two marbles are drawn at random, what is the probability that both are red ?

1. 3/7
2. 1/2
3. 2/11
4. None of the these

Correct Option: D

Total number of possible outcomes
= n(S) = ¹²C₂ = (12 x 11)/2 = 66

Total number of favorable events
= n(E) = ⁴C₂
= (4 x 3) / (2 x 1) = 6
∴ Required probability = 6/66 = 1/11