Question

50 A bag contain 5 red balls, 6 blue balls & 8 Pink balls, 1
bau is drawn at random & replace with 3 pink balls. What
is the prob. that the first ball drawn was either red or blue
in colour & the second ball drawn was pink in color.
a) 12/21
b) 13/17
c) 11/30
4) none ​

Answer 1

Answer:

11/36

Step-by-step explanation:

PROBABILITY. : Total number of favourable outcomes / total number of outcomes

Total balls:18

(case:1).A probability of one (first)ball drawn was either red or blue is (4C1+6C1)/18C1=10/18.

(case ii):replace with 3 pink balls.

total balls are=20(17+3).

Now probability of the second ball drawn was pink in colour is 11C1/20C1=11/20.

Now total probability is (first ball and(*)second ball) 10/18*11/20=11/36..

Hope answer helps you…