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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:

Option :

Answer:Option 1

Explanation:

Solution:
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.LetE = eventofgettingallthe3redballsn(E)=5C3=5C2=(5×4)(2×1)=10.P(E)=n(E)n(S)=10455=291.



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