document.write( "Question 33696: I have been working and reworking this problem all night and day; please help if possible! Thanks in advance
\n" ); document.write( "Solve by any method and show equations and major steps:
\n" ); document.write( "Computerwarehouse.com charges $3 for shipping orders up to 10 lb, $5 for orders from 10 lb to 15 lb, and $7.50 for orders of 15 lb or more. One day shipping charges for 150 orders totaled $680. The number of orders under 10 lb was three times the number of orders weighing 15 lb or more. Find the number of packages shipped at each rate. \n" ); document.write( "

Algebra.Com's Answer #20111 by Paul(988) $\"\"$ $\"About$

You can put this solution on YOUR website!
Under 10lb = 3x
\n" ); document.write( "15 lb = x
\n" ); document.write( "from 10lb 10 15lb = y
\n" ); document.write( "3x+x+y=150
\n" ); document.write( "y=150-4x
\n" ); document.write( "Max value is 150:
\n" ); document.write( "Under 10lb the charge is $3
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From 10lb to 15lb the charge is $5
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document.write( "More that 15lb the charge is $7.5
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document.write( "Total profit: $680
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document.write( "Equation:
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document.write( "3(3x)+5(y)+7.5(x)=680
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document.write( "9x+5y+7.5x=680
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document.write( "16.5x+5(150-4x)=680
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document.write( "16.5x-20x=680-750
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document.write( "-3.5x=-70
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document.write( "x=20
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document.write( "3(20)=60
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document.write( "y=150-4(20)
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document.write( "y=70
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document.write( "Hence, for 15lb or more their were 20 pakages, for 10lb to 15lb their were 70 pakages and for under 10lb their were 70 pakages.
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document.write( "Paul. \n" );
document.write( "

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