SOLUTION: An urn contains 7 blue, 7 yellow, and 8 gray marbles. Two marbles are randomly drawn from the urn. Find the probability the two marbles are the same color.

Question 1168146: An urn contains 7 blue, 7 yellow, and 8 gray marbles. Two marbles are randomly drawn from the urn.
Find the probability the two marbles are the same color.

Found 2 solutions by VFBundy, Boreal:
Answer by VFBundy(438) (Show Source): You can put this solution on YOUR website!
= = = =
Answer by Boreal(15235) (Show Source): You can put this solution on YOUR website!
22 marbles and choose 2.
There are 22C2 or 231 ways.
for 2 blue or 2 yellow, it is (7/22)(6/21)=42/462 each or 42/231
for 2 gray it is (8/22)(7/21)=56/432 or 28/231
So the answer is 70/231 or 0.3030
RELATED QUESTIONS
An urn contains 5 red marbles 9 blue marbles and 10 white marbles. two marbles are drawn... (answered by ewatrrr)
Suppose an urn contains 8 red, 5 white, and 7 blue marbles. If three marbles are drawn st (answered by oscargut)
Suppose an urn contains 8 red, 5 white, and 7 blue marbles. If three marbles are drawn st (answered by oscargut)
An urn contains 7 red marbles, 6 white marbles, and 8 blue marbles marbles. A child... (answered by ikleyn,math_tutor2020)
An urn contains 9 red marbles, 10 white marbles, and 5 blue marbles marbles. A child... (answered by ikleyn)
Urn A contains 4 red and 3 black marbles. Urn B contains 5 red and 7 black marbles. From... (answered by greenestamps)
One urn contains 3 read and 7 white marbles. A second urn contains 2 red and 8 white... (answered by stanbon)
One urn contains 3 red and 7 white marbles. A second urn contains 2 red and 8 white... (answered by edjones)
An urn contains 4 green , 5 blue , 2 red and 3 yellow marbles . If four marbles are drawn (answered by Edwin McCravy)