document.write( "Question 133568: Arthur can do a job in 30 minutes, Bonnie can do it in 40 minutes, and Claire can do it in 60 minutes. How long will it take them if they work together? \n" ); document.write( "
Algebra.Com's Answer #97740 by ptaylor(2198)\"\" \"About 
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Arthur can do a job in 30 minutes, Bonnie can do it in 40 minutes, and Claire can do it in 60 minutes. How long will it take them if they work together?\r
\n" ); document.write( "\n" ); document.write( "Let x=amount of time it takes them working together
\n" ); document.write( "Arthur works at the rate of 1/30 of the job per min\r
\n" ); document.write( "\n" ); document.write( "Bonnie works at the rate of 1/40 of the job per min\r
\n" ); document.write( "\n" ); document.write( "Claire works at the rate of 1/60 of the job per min\r
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\n" ); document.write( "\n" ); document.write( "Together they work at the rate of 1/30+ 1/40 +1/60 of the job per min. This equals
\n" ); document.write( "1/30 + 1/40 + 1/60= 4/120 + 3/120 + 2/120= 9/120 of the job per min\r
\n" ); document.write( "\n" ); document.write( "Now, our equation to solve is:\r
\n" ); document.write( "\n" ); document.write( "(9/120)x=1 (1 job, that is) multiply each side by 120\r
\n" ); document.write( "\n" ); document.write( "9x=120 divide both sides by 9
\n" ); document.write( "x=13 1/3 min----------------time it takes them working together\r
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\n" ); document.write( "\n" ); document.write( "Hope this helps---ptaylor \n" ); document.write( "
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