Question

A bag contains 3 white, 2 blue and 5 red balls. One ball is drawn at random from this bag. Then, the probability that the ball drawn is not red is

• A. 3/10
• B. 1/5
• C. 1/2
• D. 4/5

Hint:

Probability of an event = (Number of favorable outcomes) / (Total number of possible outcomes).
P(not A) = 1 - P(A).

Answer 1

The Correct Option is C

Number of white balls = 3. Number of blue balls = 2. Number of red balls = 5. Total number of balls in the bag = \(3 + 2 + 5 = 10\). Let E be the event that the ball drawn is not red. If the ball is not red, it must be either white or blue. Number of non-red balls = Number of white balls + Number of blue balls = \(3 + 2 = 5\). The probability of drawing a non-red ball is: \[ P(E) = \frac{\text{Number of non-red balls}}{\text{Total number of balls}} = \frac{5}{10} = \frac{1}{2} \] Alternatively: Let R be the event that the ball drawn is red. \(P(R) = \frac{\text{Number of red balls}}{\text{Total number of balls}} = \frac{5}{10} = \frac{1}{2}\). The event that the ball drawn is not red is R'. \(P(R') = 1 - P(R) = 1 - \frac{1}{2} = \frac{1}{2}\). This matches option (c). \[ \boxed{1/2} \]