Question 941416
average age of 5 students is 10 years
   sum of age of all  5 students  = average * no of students
              = 5*10
              =50
A student aged 14 drops out, then sum of ages of remaining students  =  50-14
   = 36
  average of remaining students   =  sum of remaining 4 students / no of students
                              = 36/4
                   = 9
 Result ': new average  = 9