Find the probability distribution of the number of white balls drawn in a random draw of 3 balls without replacement, from a bag containing 4 white and 6 red balls.

Let X denote the number of white balls drawn in a random draw of 3 balls.


X can take values 0,1,2 or 3.


Since bag contains 6 red and 4 white ball, i.e. at a total of 10 balls


total no. of ways of selecting 3 balls out of 10 = 10C3


For selecting 0 white balls, we will select all 3 balls from red


P(X = 0) = P (not selecting any white ball) =


For selecting 1 white ball, we will select all 2 balls from red and 1 from white


P(X = 1) =


For selecting 2 white balls, we will select all 1 ball from red and 2 from white


P(X = 1) =


For selecting 3 white balls, we will select all 0 balls from red and 2 from white


P(X = 1) =


Now we have pi and xi.


Now we are ready to write the probability distribution for X:-


The following table gives probability distribution:



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