Question 773538
Karl's school is selling tickets to a choral performance. On the first day of ticket sales the school sold 13 senior citizen tickets and 4 child tickets for a total of $255. The school took in $255 on the second day by selling 9 senior citizen tickets and 8 child tickets. Find the price of a senior citizen and the price of a child ticket. 
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Value Equations:
13s + 4c = 255 dollars
9s  + 8c = 255 dollars
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Modify for elimination::
26s + 8c = 510
9s  + 8c = 255
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19s = 255
s = $13.42 (price of a senior ticket)
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Solve for "c":
9s + 8c = 255
9*13.42 + 8c = 255
c = $16.78 (price of a child's ticket)
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Cheers,
Stan H.
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