<PRE><B>Question 251978</B>
Let the number of females be 7x
Then,the number of males is 4x
3 females and 12 males will be absent tomorrow,
So,tomorrow the number of females will be 7x-3 and the number of males is 4x-12
Given,   (7x-3)/(4x-12) = 5/2
            2(7x-3)     = 5(4x-12)
                 14x-6  = 20x-60
                     54 = 6x
                      x = 9
Total number of students tomorrow = 7x-3+4x-12
                                  = 11x-15
                                  = 11x9-15
                                  =84
  

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