From a lot of 15 bulbs which includes 5 defectives, a sample of 4 bulbs is drawn one by one with replacement.Find tje probability distribution of number of defective bulbs. Hence, find the mean of the diatribution.

Dear Student,
Please find below the solution to your problem.

et X denote the number of defective bulbs

P(X = 0) = 15C0 (10/15)⁴ = 16/81

Similarly
P(x= 1) = 32/84
P(x= 2) = 24/81
P(x= 3) =8/81
P(x= 4) = 1/81
Man of distribution = 16 + 32+ 24 + 8 +1 /81*5 = 1/5

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