SOLUTION: An urn contains 8 balls identical in every way except color. There are 4 blue balls, 3 red balls, and 1 yellow ball. a) You draw 2 balls from the urn but replace the first befor

Algebra ->  Probability-and-statistics -> SOLUTION: An urn contains 8 balls identical in every way except color. There are 4 blue balls, 3 red balls, and 1 yellow ball. a) You draw 2 balls from the urn but replace the first befor      Log On


   

Question 465346: An urn contains 8 balls identical in every way except color. There are 4 blue balls, 3 red balls, and 1 yellow ball.
a) You draw 2 balls from the urn but replace the first before drawing the second. What is the probability that both balls are red?
b) You draw 2 balls from the urn but do not replace the first before drawing the second. What is the probability that both balls are red?
c) Explain the difference (if any) in the two problems.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

8 balls: 4blue,3red,1yellow

drawing 2 balls:

with replacement: p(both red) = 3/8*3*8 = 9/64 = .1406

w/o replacement: P(both red) = 3/8*2/7 = 6/56 = 3/28 = .1071

with replacement, there is a greater chance the 2nd will be red.