- #1
zorro
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Homework Statement
The number of ways in which 4 distinct balls can be kept in 7 different boxes if each box can have atmost 1 ball are?
The Attempt at a Solution
Easy one but I need to verify my answer.
The first ball can be kept in any of the 7 boxes in 7 ways
The second ball can be kept in 6 ways...
Permuting this way 7P4 = 840
Now, since the balls are distinct, total no. of ways are 840 x 4 = 3360
But the answer says it is 840.
Who is right?