Five defective bulbs are accidently mixed with 20 good ones. It is not possible to just look at a bulb and tell whether or not it is defective. Find the probability distribution from this lot.

Given : Five defective bulbs are accidently mixed with 20 good ones.


To find : probability distribution from this lot


Formula used :



Five defective bulbs are accidently mixed with 20 good ones.


Total number of bulbs = 25


X denote the number of defective bulbs drawn


X can draw the value 0 , 1 , 2 , 3 , 4.


since the number of bulbs drawn is 4, n = 4


P(0) = P(getting a no defective bulb) = = =


P(1) = P(getting 1 defective bulb and 3 good ones) = =


P(1) = =


P(2) = P(getting 2 defective bulbs and 2 good one) =


P(2) = = =


P(3) = P(getting 3 defective bulbs and 1 good one) =


P(3) = =


P(4) = P(getting all defective bulbs) = = =


P(4) =


The probability distribution table is as follows,



1