probabilities of drawers with replacement

Question

An urn contains 5

 pink and 9

 green balls. Four balls are randomly drawn from the urn in succession, with replacement. That is, after each draw, the selected ball is returned to the urn. What is the probability that all 4

 balls drawn from the urn are green? Round your answer to three decimal places.

Answer 1

There are a total of 14 balls (5 pinks and 9 greens). 4 balls will be selected from the urn.

P(4 green balls) = (9/14)*(9/14)*(9/14)*(9/14)

= (9/14)⁴

= 6,561 / 38,416

≈ 0.1708

The probability that all 4 balls drawn from the urn are green is about 0.1708.