Question

(xiv) A bag contains 3 white, 5 black and 7 red balls, Two
balls are drawn at random. What is the probability
that they will both be red?

(a) 7/15
(b) 1/5
(c)8/15
(d)7/105​

Answer 1

Answer:

Since, total no. of balls = 7+5+3 = 15

(i) No. of balls that are red or white = 7+5 = 12

∴ Required probability =

15

12

=

5

4

(ii) No. of balls that are not black = 7+5 = 12

∴ Required probability =

15

12

=

5

4

(iii) No. of balls that are neither white nor black = 7

∴ Required probability =

15

7