An urn contains 4 red and 7 black balls. Two balls are drawn at random with replacement. Find the probability of getting (i) 2 red balls, (ii) 2 black balls, (iii) one red and one black ball.

Question

Philoid · Accepted Answer

Given an urn contains 4 red and 7 black balls

Probability of getting red ball=

Probability of getting black ball=

(i) two red balls

P(getting two getting red balls)=P(R)*P(R)

(ii) two black balls

P(getting two blue balls)=P(B)*P(B)

(iii) first red and second black ball.

P( getting one red and one black ball)=P(R)*P(B)+P(B)*P(R)