A bag contains 4 red and 7 blue balls. What is the probability of drawing a blue ball if the first ball drawn is red? The balls drawn are replaced into the bag.

Category: QuestionsA bag contains 4 red and 7 blue balls. What is the probability of drawing a blue ball if the first ball drawn is red? The balls drawn are replaced into the bag.
Editor">Editor Staff asked 11 months ago

A bag contains 4 red and 7 blue balls. What is the probability of drawing a blue ball if the first ball drawn is red? The balls drawn are replaced into the bag.
 
(a) \frac {8}{11}
 
(b) \frac {7}{11}
 
(c) \frac {4}{11}
 
(d) \frac {7}{4}
 
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1 Answers
Editor">Editor Staff answered 11 months ago

Correct answer is (b) \frac {7}{11}
 
The explanation is: Total number of balls = 4 + 7 = 11
 
The probability of the first ball to be red = \frac {4}{11}
 
The probability of drawing blue ball as the second ball out with replacement = \frac {7}{11}