<PRE><B>Question 85650</B>
S+NS=311 THEN S=311-NS
.50S+1.50NS=385.50 NOW SUBSTITUTE (311-NS)FOR S AND SOLVE FOR NS.
.50(311-NS)+1.50NS=385.50
155.5-.5NS+1.5NS=385.50
1NS=385.50-155.50
NS=230 NUMBER OF NON-STUDENT TICKETS SOLD.
311-230=81 STUDENT TICKETS SOLD.
PROOF
.50*81+1.50*230=385.50
40.50+345=385.50
385.50=385.50

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