Question 970226
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P=original price (last year); N=number of tickets (last year)
PN=$6300
N=$6300/P
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{{{(N+48)(P-$3)=$5970}}} Substitute for N.
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{{{(($6300/P)+48)(P-$3)=$5970}}}
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{{{$6300-$18900/P+48P-$144=$5970}}}
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{{{$6156-$18900/P+48P=$5970}}} Subtract $6156 from each side.
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{{{-$18900/P+48P=-$186}}} Convert to common denominator.
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{{{-18900/P+(48P^2)/P=(-$186P)/P}}} Multiply by P.
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{{{-$18900+48P^2=-$186P}}} Add $186P to each side.
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{{{48P^2+$186P-$18900=0}}}
*[invoke quadratic "P", 48, 186, -18900 ]
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The price of a prom ticket last year was $18, so:
$6300/$18=350 There were 350 tickets sold last year.
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The price of the prom this year was $15 ($18-$3=$15)
$5970/$15=398 There were 398 tickets sold this year.(48 more than last year)