VJesus12 wrote:A bag contains only 3 different colors and at least one ball of red, white and blue color. If the number of balls of each color is distinct and red colored balls are more than each of the other two colors, what is the probability of picking red ball?

(1) the number of blue and white balls is half of the total number of balls.
(2) there are 3 red colored balls.

The OA is the option D.

I need some help here. Please, could someone explain this DS question? Thanks.

We have to determine the probability of picking a red ball.

Let's take each statement one by one.

(1) The number of blue and white balls is half of the total number of balls.

The statement itself means that the probability of picking a red ball = 1/2.

Anyway, let's take the traditional way of solving the question.

Say the number of blue and white balls is x then the total number of red balls = x.

The probability of picking a red ball = (Number of red balls) / (Total number of balls) = x/2x = 1/2. Sufficient.

(2) There are 3 red colored balls.

Since the number of red balls is greater than that of white and that of blue balls, the number of white and that of blue balls would be either 2 or 1.

Since the number of balls of each color is distinct, if the number of white balls = 2, the number of blue balls = 1, or vice versa.

=> The number of white plus blue balls = 2 + 1 = 3.

The probability of picking a red ball = (Number of red balls) / (Total number of balls) = 3/(3 + 3) = 1/2. Sufficient.

The correct answer: D

Hope this helps!

-Jay
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