sumasajja wrote:Combination
7 identical balls have to be distributed among 4 people. How many ways can the balls be distributed so that each person gets at least 1 ball and one person gets more than 2 balls?
A) 7 B) 28 c) 81 d)2401 e) none of these
The approaches above are great. Below is one more.
One person gets 3 balls:
In order for each person to get at least 1 ball, the balls must be distributed 3-2-1-1.
Number of ways to arrange the 4 elements {3,2,1,1} = 4!/2! = 12.
One person gets 4 balls:
In order for each person to get at least 1 ball, the balls must be distributed 4-1-1-1.
Number of ways to arrange the 4 elements {4,1,1,1} = 4!/3! = 4.
Total possible distributions = 12+4 = 16.
The correct answer is
E.
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