SOLUTION: Five white and four black balls are arranged in a row. What is the probability that the end balls are of different colors? Thank You so much ..

Algebra.Com
Question 1177214: Five white and four black balls are arranged in a row. What is the probability that the end
balls are of different colors?
Thank You so much ..
Found 2 solutions by ewatrrr, greenestamps:
Answer by ewatrrr(24785)   (Show Source): You can put this solution on YOUR website!

Hi
 9 balls:  5W and 4Bk  (9! ways of arranging 9 Balls)

I. Reserve one of each color for the end spots...leaving 7 balls
The 7 balls can be arrange in 7! ways.

II> P(different colors on both ends = 2*7!/9! (white or black on either end)
 2*7!/9!= 2/9*8 = 1/9*4 = 1/36 = .0278

Wish You the Best in your Studies.


Answer by greenestamps(13200)   (Show Source): You can put this solution on YOUR website!


The arrangement of the other 7 balls has nothing to do with the problem.

P(different colors on each end) = P((white first AND black last) OR (black first AND white last))
RELATED QUESTIONS

Five white and four black balls are arranged in a row. What is the probability that the... (answered by jrfrunner)
Five balls are drawn from a bag containing six white and four black balls? What is the... (answered by dkppathak)
A box contains 13 balls out of which 8 are white balls and 5 are black balls. Three balls (answered by Boreal)
In a box there are 500 colored balls: 75 black, 150 green, 175 red, 70 white and 30... (answered by rothauserc)
Please help? Two urns contain each contain white balls and black balls. Urn 1 contains... (answered by fractalier,Fermat,AnlytcPhil)
A lot of machine contains balls of four different colors. 1/3 of the balls are black, 2/9 (answered by fractalier)
Two urns contain 4 white and 6 black balls and 3 white and 8 black balls respectively. If (answered by greenestamps)
Two urns contain 4 white and 6 black balls and 3 white and 8 black balls respectively. If (answered by Boreal)
A bag contains three black balls,four white balls and five red balls.Three balls are... (answered by ikleyn)