the average of 1 ticket will be 43/7
  
 A-average of tickets
 G-General Admission tickets
 R-Reserved Seat tickets
  
 G               A                           R
 4_______43/7____________9
     15/7                 20/7
  
  
 distance from G to A is:
 lG-Al=l4-43/7l=15/7 
  
 distance from R to A:
 lR-Al=l9-43/7l=20/7
  
 So the ratio     G           :             R
                       20/7                    15/7
                            20/7:15/7=4:3
                         4                          3
 SO there was:
 4 General admission ticket for $4: 4x4=16
 3  Reserved Seat tickets for $9: 3x9=27
  
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