Fifty balls are numbered 1 to 50 and red dot is painted on those balls that are a multiple of 8. the balls are mixed into a bag and on call is randomly chosen. what is the probability that the ball is numbered with a multiple of 10 or has a red dot?
Total number of balls = 50 Balls numbered as multiple of 10 = 5 Balls with red dot on them = 6 Balls numbered as multiple of 10 and having red dot on them = 1 (i.e. Ball with number 40 on it)
Probability of Ball being numbered as multiple of 10 = P(T) = 5/50 = 1/10
Probability of Ball being marked by the dot = P(D) = 6/50 = 3/25
Probability of Ball being numbered as multiple of 10 and having a red dot on it = P (T ∩ D) = 1/50
The "or" ,"union" of two events can be expressed as: