Question 106802
Tickets for a play at the community theater cost $20 for an adult and $4 for a child.  If 140 tickets were sold and the total receipts were $2160, how many of each type of ticket were sold?
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x=adult tickets
y=child tickets
x+y=140
20x+4y=2160
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x=140-y
20(140-y)+4y=2160
2800-20y+4y=2160
-16y=-640
y=40
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x+40=140
x=140-40
x=100
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so the were 100 adult tickets and 40 child tickets sold
:)