Discussion :: Probability
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A bag contains 4 white, 5 red and 6 blue balls. Three balls are drawn at random from the bag. The probability that all of them are red, is:
Answer : Option C
Explanation :
Let S be the sample space.
Then, n(S) | = number of ways of drawing 3 balls out of 15 |
= 15C3 |
= (15∗14∗13)(3∗2∗1)
= 455
Let E = event of getting all the 3 red balls.
n(E) = 5C3 = 5C2 =(5∗1)(2∗1)=10
P(E) =n(E)n(S)=10455=221
10/455 is 2/91.