adult tickets for a play cost $5.50 and a child ticket cost $3.50. They sold 550 tickets and collected $2139.00. How many adult tickets sold

Answer 1

x-number the adult tickets
y-number the child tickets

x+y=550
5.50*x + 3.50*y =2139.00
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y=550-x
5.50*x +3.50*(550-x) =2139.00
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5.50*x +3.5*550- 3.50*x =2139.00
(5.5-3.5)*x +1925.00 = 2139.00
2*x=2139.00-1925.00
2*x=214
x=214/2
x=107
107 adult ticket were sold