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Re: number of onto functions
Posted:
May 19, 2012 11:22 AM


> Q: In how many ways can 7 different jobs be assigned > to 4 different employees so that each employee gets > atleast one job and the best employee gets the > toughest job. > Mahesh,
I tackled it this way:
Let the 7 jobs be T(oughest) + 6 and let the 4 employees be B(est) + 3
Then B and T always go together, plus 6 other jobs between 4 employees who always get at least 1 job each.
Allocate 6 jobs one each to the other 3 employees in 6.5.4 ways, with 3 jobs over.
Allocate these 3 jobs to 4 employees in 4.4.4 ways, because they need not go to different employees.
So answer = 1 . 6.5.4 . 4.4.4 = 7680 I think.
Regards, Peter Scales.
Message was edited by: Peter Scales on 19 May.



