document.write( "Question 359544: An electric power company charges its consumers $ 0.40 per kilowatt for the first 100 kilowatts in a month, $ 0.50 per kilowatt for the second 100 kilowatts, and $ 0.60 for each additional kilowatt beyond. Mary pays $ 120 for electricity used in last month.How much electricity did her family consume in the month? \n" ); document.write( "
Algebra.Com's Answer #256592 by ankor@dixie-net.com(22740)\"\" \"About 
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An electric power company charges its consumers $ 0.40 per kilowatt for the
\n" ); document.write( " first 100 kilowatts in a month,
\n" ); document.write( " $ 0.50 per kilowatt for the second 100 kilowatts,
\n" ); document.write( " and $ 0.60 for each additional kilowatt beyond.
\n" ); document.write( " Mary pays $ 120 for electricity used in last month.
\n" ); document.write( "How much electricity did her family consume in the month?
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\n" ); document.write( "Let x = total no. of kwh used in a month
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\n" ); document.write( ".6(x-200) + .5(100) + .4(100) = 120
\n" ); document.write( ".6x - 120 + 50 + 40 = 120
\n" ); document.write( ".6x - 30 = 120
\n" ); document.write( ".6x = 120 + 30
\n" ); document.write( ".6x = 150
\n" ); document.write( "x = \"150%2F.6\"
\n" ); document.write( "x = 250 kwh used
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\n" ); document.write( "See if this is true
\n" ); document.write( ".4(100) = 40
\n" ); document.write( ".5(100) = 50
\n" ); document.write( ".6(50) = 30
\n" ); document.write( "---------------
\n" ); document.write( "total$ = 120
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\n" ); document.write( "Did this make sense to you? \n" ); document.write( "
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