An urn contains seven red balls, seven white balls, and seven blue balls, and sample of four balls is drawn at random without replacement.

Compute the probability that all of the balls in the sample are the same color.

Question

An urn contains seven red balls, seven white balls, and seven blue balls, and sample of four balls is drawn at random without replacement.

Compute the probability that all of the balls in the sample are the same color.

perl · Answer

Probability ( 4 balls of same color) 
= P ( RRRR or WWWW or BBBB ) 
=P(RRRR) + P(WWWW) + P(BBBB)

can you calculate those separately

perl · Answer

P(RRRR) = 7/21 * 6/20 * 5/19*4/18

perl · Answer

same goes for P(WWWW) , and P(BBBB)

perl · Answer

R = red ball
W = white ball
B = blue ball

anonymous · Answer

is it 0.0174 final answer. for individual is 0.0058

anonymous · Answer

i tried it but it is wrong

perl · Answer

does it say to estimate

perl · Answer

the exact value is 1/57

perl · Answer

3* 7/21 * 6/20 * 5/19*4/18 = 1/57

anonymous · Answer

thank you perl

anonymous · Answer

its correct now