Question

If there are a probability of 20% to get a red ball and 80% to get a blue ball. What is the probability to get exactly 1 red ball when picking out three balls without putting them back?

Answer 1

With this information, we must assume that there is an infinite number of balls; therefore, the answer is

(3 c 1)(0.20)(0.80)(0.80) = 0.384

Answer 2

Probability of a red 0.20
Probability of a no red 0.80
Then: probability of just one red of tree balls is
(0.20)(0.80)(0.80) = (0.80)(0.20)(0.80) = (0.80)(0.80)(0.20) = 0.384