A bag contains 4 white , 7black and 5 red balls. 4 balls are drawn with replacement. What is probability that at least two are white?

Explanation

Given events are

A=A white ball in the first draw

B=A black ball in the second draw

C=A red ball in the third draw

Now,

P(A)`=frac{4}{16}=frac{1}{4}`

`P(B / A)=frac{7}{15}`

`P(C / A cap B)=frac{5}{14}`

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