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For a saturday matinee, adult tickets cost $5.50 and kids under 12 pay only $4.00. if 70 tickets are sold for a total of $310, how many of the tickets were adult tickets and how many were sold to kids under 12?

Respuesta :

20 adults and 50 kids.
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Ax+By=C [Use the standard form of a linear equation]
x+y=C so, x+(C-x)=C [also use this formula]
.
$5.50x+$4.00y=$310 [plug-in the values]
Since x+(C-y)=C, than x+y=70 or x+(70-x)=70
.
5.50x+4.00(70-x)=310 [substitute (70-x) for y and simplify]
5.50x+280-4x=310
5.50-4=310-280 [solve for x]
1.5x=30
x=20 adults
and
y=(70-x)=70-20=50 kids under 12.

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