Question 1015684
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A=number of adult tickets; S=number of student tickets
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A+S=150
A=150-S . Use this to substitute for A below.
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$1A+$0.75S=$140 Substitute for A.
$1(150-S)+$0.75S=$140
$150-$1S+$0.75S=$140
-$0.25S=-$10
S=40
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ANSWER 1: 40 student tickets were sold.
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A=150-S=150-40=110
ANSWER 2: 110 adult tickets were sold.
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CHECK:
$1A+$0.75S=$140
$1(110)+$0.75(40)=$140
$110+$30=$140
$140=$140
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