A Receptacle contains 3violet, 4purple and 5 black balls. Three balls are drawn at random from the receptacle. The probability that all of them are purple, is: A)3/55 B)7/55 C)1/55 D)9/55

1 Answer

Answer :

Answer: C)

Let S be the sample space.

Then, n(S) = number of ways of drawing 3 balls out of 12 = 12C3 = 220

Let E = event of getting all the 3 purple balls.

n(E) = 4C3= 4

P(E) = n(E)/n(S) = 4/220 = 1/55

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