Question

An urn contains 10 red balls, 7 green balls, and 3 yellow balls. Draw 5 balls.

What's the probability that you draw 2 red, 2 green, and 1 yellow?

(Same experiment as above) What's the probability that you draw 2 red, 1 green, and 2 yellow?

Answer 1

Part a)

n = 5

We can select 2 red balls from 10 red balls by ways = 45 ways

Similarly, for green balls = 21 ways

for yellow balls = 3 ways

Total ways to select 5 balls from 10 + 7 + 3 = 20 balls is = 15504 ways.

Required probability is ( 45 * 21 * 3 ) / 15504 = 0.1829

Part b)

Red balls ways = 45 ways

Green balls   = 7 ways

Yellow balls = 3 ways

Required probability is ( 45 * 7 * 3 ) / 15504 = 0.0610