Dear Kesho,
It is really a great problem. is the answer 7?
Would you give me the referrence form where you have taken it.
Thanking you-
smbabu
sabyasachymistry@yahoo.com
I also concur with 7 because the worst case sequence is R G B R G B
Dear Kesho i believe that the way to get the answer is as follows:
No. of marbles = 18
No. of Red marbles = 8
No. of Green marbles = 4
No. of Black marbles = 6
Now,
The probability of picking up 3 red's = 1/R = 3/8
The probability of picking up 3 greens = 1/G = 3/4
The probability of picking up 3 blacks = 1/B = 3/6 or 1/2
Hence the probability of picking up 3 of the same colour is =
1/P = 1/R*1/G*1/B
= 3/8*3/4*1/2
= 9/64
Finally,
1/P = 9/64
P = 64/9
P = 7.111111 ~ 7
Hence, P = 7
Hope this answers the Q?
Please do correct me if i am wrong.
"Give a man a fish, and he'll eat for a day. Teach him how to fish and he'll eat forever- Chinese Proverb"
Dear kesho,
Thank you very much. is 'MTAB 1380' available at internet?
-
smbabu
Bookmarks