document.write( "Question 1094144: A company can produce a doll at a cost of $5 per dolls. When the company sells the dolls at a price of $40 they can sell 400 dolls each week. It is estimated that for every $0.50 decrease in the price, they can sell 20 more dolls.
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Algebra.Com's Answer #708741 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
Let \"+P+\" = profit per week
\n" ); document.write( "Let \"+n+\" = the number of $.50 decreases in price
\n" ); document.write( "[ profit ] = [ income ] - [ cost ]
\n" ); document.write( "\"+P+=+%28+40+-+.5n+%29%2A%28+400+%2B+20n+%29+-+%28+400+%2B+20n+%29%2A5+\"
\n" ); document.write( "\"+P+=+%28+40+-+5+-+.5n+%29%2A%28+400+%2B+20n+%29+\"
\n" ); document.write( "\"+P+=+%28+35+-+.5n+%29%2A%28+400+%2B+20n+%29+\"
\n" ); document.write( "\"+P+=+14000+-+200n+%2B+700n+-+10n%5E2+\"
\n" ); document.write( "\"+P+=+-10n%5E2+%2B+500n+%2B+14000+\"
\n" ); document.write( "\"+P+=+-n%5E2+%2B+50n+%2B+1400+\"
\n" ); document.write( "-------------------------------------
\n" ); document.write( "The n-value of the maximum is at:
\n" ); document.write( "\"+n%5Bmax%5D+=+-b%2F%282a%29+\"
\n" ); document.write( "\"+a+=+-1+\"
\n" ); document.write( "\"+b+=+50+\"
\n" ); document.write( "\"+n%5Bmax%5D+=+-50%2F%282%2A%28-1%29%29+\"
\n" ); document.write( "\"+n%5Bmax%5D+=+25+\"
\n" ); document.write( "and
\n" ); document.write( "\"+P%5Bmax%5D+=+-10%2A25%5E2+%2B+500%2A25+%2B+14000+\"
\n" ); document.write( "\"+P%5Bmax%5D+=+-6250+%2B+12500+%2B+14000+\"
\n" ); document.write( "\"+P%5Bmax%5D+=+20250+\"
\n" ); document.write( "The maximum weekly profit is $20,250
\n" ); document.write( "The price that will maximize the profit is:
\n" ); document.write( "\"+40+-+.5n+\"
\n" ); document.write( "\"+40+-+.5%2A25+\"
\n" ); document.write( "\"+40+-+12.5+=+27.5+\"
\n" ); document.write( "$27.50 per doll
\n" ); document.write( "------------------------------------------
\n" ); document.write( "check:
\n" ); document.write( "Here's the plot:
\n" ); document.write( "\"+graph%28+400%2C+400%2C+-10%2C+60%2C+-2000%2C+25000%2C+-10x%5E2+%2B+500x+%2B+14000+%29+\"
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