firas92 wrote:
Find the number of ways in which 5 men can watch 4 movies such that each movie is watched by at least one person and no one can watch more than one movie.
A. 150
B. 240
C. 360
D. 480
E. 120
One way not to go wrong is to first get the persons in propergrouping..
So, get the way two people can be one group and rest all in single --- 5C2=10
Next we have persons in 2-1-1-1 groups and each such combination can watch 4 different movies in 4! ways..
Total ways = 5C2*4!=\( \frac{5*4}{2} *4!=10*24=240 \)
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