Twelve balls are placed in three boxes. The probability that the first box contains three balls is
Twelve balls are placed in three boxes. The probability that the first box contains three balls is
A. `(110)/(9)((2)/(3))^(10)`
B. `(9)/(110)((2)/(3))^(10)`
C. `(.^12C_(3))/(12^(3))xx2^(9)`
D. `(.^(12)C_(3))/(3^(12))`
1 Answers
Correct Answer - A
Since each ball can be placed in any one of the 3 boxes, therefore there are 3 ways in which a ball can be palced in any one of the three boxes. Thus, there are `3^(12)` ways in which 12 balls can be placed in 3 boxes. The number of ways in which 3 balls out of 12 can be put in the box is `.^(12)C_(3)`. The remaining 9 balls can be placed in 2 boxes in `2^(9)` ways. So, required probability is
`(.^(12)C_(3))/(3^(12)) 2^(9) = (110)/(9) ((2)/(3))^(10)`