Question 495665
I set up simultaneous equations

25x + 18y = 441
20x + 20y = 420
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I multiplied the first equation by -20 
I multiplied the second equation by 25
-500x + -360y = -8820
500x + 500y = 10500
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  140y  = 1680
y = 12
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Plugging in y, I solved for x.
25x + 18(12)  = 441
25x + 216 = 441
25x = 225 = 9
x = 9
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Now I checked in the second equation.
20(9) = $180
20(12) = $240
180 + 240 = $420
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Checking in the first equation.
25(9) = $225
18(12) = $216
$225 + $216 = $441
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This does check.
Cleomenius.