Question

a bag contains 4 red 5 black and 6 white balls. a ball is drawn from the bag at random. find the probability that the ball drawn is : (i) white (ii) red (iii) not black (iv) red or white

Answer 1

1. 6/15
2.4/15
3.3/5
4.1/3

Answer 2

Question

1. A bag contains 4 red, 6 black and 5 white balls. A ball is drawn at random from the bag. Find the probability that the ball drawn is :

(i) white                       (ii) not black                         (iii) red or black

Solution

Total number of possible outcomes = Total number of balls

                                                       = 4 red balls + 6 black balls + 5 white balls

                                                                   = 15 balls = 15

(i) For a white ball

    Number of favourable outcomes = Number of white balls = 5

$\rm{Answer => Required \: probability =\dfrac{5}{15}=\dfrac{1}{3}}$

(ii) For not a black ball

      Number of favourable outcomes = Number of red balls + Number of white balls

                  ⇒ 4 + 5 = 9

$\rm{Answer => Required \: probability=\dfrac{9}{15}=\dfrac{3}{5}}$            

(iii) For red or black ball

     Number of favourable outcomes = Number of red balls + Number of black balls

                           ⇒ 4 + 6 = 10

$\rm{Answer => Required \: probability=\dfrac{10}{15}=\dfrac{2}{5}}$