document.write( "Question 375974: MACHINE A TAKES 36 HOURS TO DO A JOB THAT MACHINE B DOES IN 24 HOURS.IF MACHINE RUNS FOR 12 HRS. BEFORE MACHINE B IS TURNED ON, HOW LONG WILL IT TAKE BOTH MACHINES RUNNING TOGETHER TO FINISH THE JOB IF THEY WORK TOGETHER? \n" ); document.write( "
Algebra.Com's Answer #267463 by nerdybill(7384)\"\" \"About 
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MACHINE A TAKES 36 HOURS TO DO A JOB THAT MACHINE B DOES IN 24 HOURS.IF MACHINE RUNS FOR 12 HRS. BEFORE MACHINE B IS TURNED ON, HOW LONG WILL IT TAKE BOTH MACHINES RUNNING TOGETHER TO FINISH THE JOB IF THEY WORK TOGETHER?
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\n" ); document.write( "Since mach A ran for 12 hours, the portion of the job done is:
\n" ); document.write( "12(1/36) = 12/36 = 1/3 of the job completed before mach B starts
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\n" ); document.write( "Let x = time (hrs) for mach A/B to complete job
\n" ); document.write( "then\r
\n" ); document.write( "\n" ); document.write( "x(1/36 + 1/24) = 1 - 1/3\r
\n" ); document.write( "\n" ); document.write( "x(1/36 + 1/24) = 3/3 - 1/3\r
\n" ); document.write( "\n" ); document.write( "x(1/36 + 1/24) = 2/3\r
\n" ); document.write( "\n" ); document.write( "multiplying both sides by 3:\r
\n" ); document.write( "\n" ); document.write( "x(1/12 + 1/8) = 2\r
\n" ); document.write( "\n" ); document.write( "multiplying both sides by 24:\r
\n" ); document.write( "\n" ); document.write( "x(2 + 3) = 48\r
\n" ); document.write( "\n" ); document.write( "x(5) = 48\r
\n" ); document.write( "\n" ); document.write( "x = 48/5\r
\n" ); document.write( "\n" ); document.write( "x = 9.6 hours\r
\n" ); document.write( "\n" ); document.write( "or\r
\n" ); document.write( "\n" ); document.write( "x = 9 hours and 36 minutes
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