Question:
A bag contains 3 red balls and 5 black balls. A ball is drawn at random from the bag. What is the probability that the ball drawn is :
(i) red
(ii) black
Solution:
GIVEN: A bag contains 3 red, and 5 black balls. A ball is drawn at random
TO FIND: Probability of getting a
(i) red ball
(ii) white ball
Total number of balls 
(i) Total number red balls are 3
We know that PROBABILITY = 
Hence probability of getting red ball is equal to 
(ii) Total number of black ball are 5
We know that PROBABILITY =
Hence probability of getting black ball 