Question

Marks: 1
Question 2:
An urn contains 4 red balls and 6 black balls. A sample of 4 balls is selected from the urn
without replacement. Let X be the number of red balls contained in the sample, then find the
probability distribution for X.​

Answer 1

Answer:

Let X denote the number of blue balls in a sample of 3 balls drawn from a bag containing 4 red and 3blue balls. Then, X can take values 0,1,2 and 3

So,

P(X=0)=P (no blue ball)

=74×74×74=34364

P(X=1)=P(1 blue ball)

=73×74×74+74×73×74+74×74×73=343144

P(X=2)=P(2 blue balls)

=73×7