Question

A bag contains 10 red, 5 blue and 7 green balls. A ball is drawn at random. Find the probability of this ball being a red ball.

Answer 1

No. of red ball = 10

No. of blue ball = 5

No. of green balls = 7

If a ball is drawn out of 22 balls (5 blue + 7 green + 10 red), then the total number of outcomes are

n(S) = 22

Let E₁ = Event of getting a red ball

∴ n(E₁) = 10

∴ Required probability = `(n(E_1))/(n(S)) = 10/22 = 5/11`