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how many ways we can divide mn members into 1.m groups2.m persons

Profile image of SIVA BEHARA
14 Years agoGrade Upto college level
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1 Answer

Profile image of Arun
6 Years ago
Let us understand this by considering  
 mn 
  number of alphabets, of which  
 n 
  number of groups exist.
∴ No. of alphabets in each group
n
mn
​ 
 =m
Now, if there are  
 mn 
  number of alphabets, of which  
 m 
  alphabets are identical and such identical groups are  
 n 
 , then number of arrangements of these alphabets = 
m!×m!×m!....n(times)
(mn)!
​ 
 
(m!) 
n
 
(mn)!
​ 
 
 
So, this is the number of distribution of  
 mn 
  things into  
 n 
  equal groups.
Now, division is just the number of selection and not the arrangements.
∴ No. of ways of dividing = 
(m!) 
n
 n!
(mn