is there a fast way to solve this problem? tickets to a benefit concert were sold at $80 and $50 a piece respectively. the total receipts being $6200. if twice as many 80ticket and half as many 50ticket had been sold, the receipts would have been $7900. how many $80 tickets were sold?

Question

amistre64 · Answer

80a+50b = 6200
2(80a) + (50b)/2 = 7900


  80a + 50b = 6200 ; *-2
160a + 25b = 7900


-160a -100b = -12400
  160a + 25b =     7900
----------------------
             -75b =  -4500

             b@50 = 4500/74 ; if i did it right

amistre64 · Answer

i spose the smarter step would have been to eliminate the b and solve for a :)

amistre64 · Answer

80a + 50b = 6200
160a + 25b = 7900 ; *-2

    80a +50b =     6200
-320a  -50b = -15800
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-240a          = -  9600 
   
                  a = 9600/240  perhaps?

amistre64 · Answer

dbl chk 40 @ $80

anonymous · Answer

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