Question

A bag contains 8 red, 6 white and 4 black balls. A ball is drawn at random from the bag. Find the probability that the drawn ball is

(i) Red or white

(ii) Not black

(iii) Neither white nor black

Answer 1

Total no. of possible outcomes = 8 + 6 + 4 = 18 {8 red, 6 white, 4 black}

(i) E ⟶ event of getting red or white ball

No. of favourable outcomes = 4 {4 black balls}

P(E) = 4/18 = 2/9

(Bar E) ⟶event of not getting black ball

P(Bar E)=1−P(E)=1−2/9 = 7/9

(ii) E ⟶ event of getting neither white nor black.

No. of favourable outcomes = 15 – 6 – 4 = 8 {Total balls – no. of white balls – no. of black balls}

P(E) = 8/18 = 4/9