Ten balls are to be randomly chosen from an urn containing 8 red, 10 green and 12 yellow balls. a) What is the probability that at least one yellow ball is chosen?

0.9985

Step-by-step explanation:

8 red balls

10 green balls

12 yellow balls.

Re: probability = favourable outcome/possible outcome.

To get probability of at least one yellow ball being chosen, we first get the probability that no yellow ball is chosen and subract the answer from 1.

Doing this,

Favourable outcome = number of ways to pick the balls without considering a yellow ball = 18C10

Possible outcome = number of ways to pick 10 balls without restrictions = 30C10

Probability of not choosing a yellow ball = (18C10)/(30C10)

= 43758/3.005 * 10^7

=0.0015.

Hence, probability of choosing at least one yellow ball = 1 - 0.0015 = 0.9985.