Let’s assume x number of adults and 2200-x kids went to the expo.

 

Admission charges to the Expo would amount to 4x + (2200-x) (1.5) = 5050

 

Simplifying this equations, we get  2.5x + 3300 = 5050

 

                                                                2.5x = 1750

 

                                                                   X= 700 adults

                                                          And  hence 1500 Kids     Answer

 

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