document.write( "Question 675176: If 4 persons can clean 1 house in 1 hour, how long will it take 3 persons to clean the same house \n" ); document.write( "
Algebra.Com's Answer #419628 by Edwin McCravy(20054)\"\" \"About 
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document.write( "The LCM of 3 hours and 4 hours is 12 hours.\r\n" );
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document.write( "Since 4 persons can clean 1 house in 1 hour, then 3 times as many\r\n" );
document.write( "persons, or 12 persons, can clean 1 house in 1/3 the time or 20 \r\n" );
document.write( "minutes.  Therefore, 1/4 as many persons as 12, or 3 persons will \r\n" );
document.write( "take 4 times as long as 12 will take, or 80 minutes, or 1 hour and \r\n" );
document.write( "20 minutes.\r\n" );
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document.write( "Or if you prefer you can use the job-worker-time formula, which is:\r\n" );
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document.write( "\"%28W%5B1%5DT%5B1%5D%29%2FJ%5B1%5D\"\"%22%22=%22%22\"\"%28W%5B2%5DT%5B2%5D%29%2FJ%5B2%5D\"\r\n" );
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document.write( "where\r\n" );
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document.write( "W1 = the number of workers in the first situation.\r\n" );
document.write( "T1 = the number of time units (hours in this case) in the first situation.\r\n" );
document.write( "J1 = the number of jobs in the first situation.\r\n" );
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document.write( "W2 = the number of workers in the second situation.\r\n" );
document.write( "T2 = the number of time units (hours in this case) in the second situation.\r\n" );
document.write( "J2 = the number of jobs in the second situation.\r\n" );
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document.write( "W1 = 4            W2 = 3     \r\n" );
document.write( "T1 = 1            T2 = the unknown quantity \r\n" );
document.write( "J1 = 1             J2 = 1\r\n" );
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document.write( "[There was only 1 house, so the number of jobs in both situations is 1.\r\n" );
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document.write( "\"%28W%5B1%5DT%5B1%5D%29%2FJ%5B1%5D\"\"%22%22=%22%22\"\"%28W%5B2%5DT%5B2%5D%29%2FJ%5B2%5D\"\r\n" );
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document.write( "\"%284%2A1%29%2F1\"\"%22%22=%22%22\"\"%283%2AT%5B2%5D%29%2F1\"\r\n" );
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document.write( "     4 = 3T2\r\n" );
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document.write( "Divide both sides by 3\r\n" );
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document.write( "      \"4%2F3\" = T2\r\n" );
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document.write( "      \"1%261%2F3\" = T2\r\n" );
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document.write( "Answer \"1%261%2F3\" hours or 1 hour and 20 minutes.\r\n" );
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document.write( "Edwin
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