document.write( "Question 508350: Mary, sue and bill work at a motel. If each worked alone, it would take mary 10 hours, sue 8 hours and bill 12 hours. One day Mary came to work early and she had cleaned for 2 hours when Sue and bill arrived all three finished the job. How long did they take to finish? \n" ); document.write( "
Algebra.Com's Answer #340964 by lwsshak3(11628)\"\" \"About 
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Mary, sue and bill work at a motel. If each worked alone, it would take mary 10 hours, sue 8 hours and bill 12 hours. One day Mary came to work early and she had cleaned for 2 hours when Sue and bill arrived all three finished the job. How long did they take to finish?
\n" ); document.write( "**
\n" ); document.write( "Mary's work rate=1/10
\n" ); document.write( "Sue's work rate=1/8
\n" ); document.write( "Bill's work rate=1/12
\n" ); document.write( "..
\n" ); document.write( "let x=hours all three took to finish the job
\n" ); document.write( "work done = hours on the job*work rate
\n" ); document.write( "(x+2)(1/10)+x/8+x/12=100%=1
\n" ); document.write( "LCD:10*8*12=960
\n" ); document.write( "96(x+2)+120x+80x=960
\n" ); document.write( "96x+192+120x+80x=960
\n" ); document.write( "296x=960-192
\n" ); document.write( "296x=960-192=768
\n" ); document.write( "x=768/296=2.59 hrs (rounded)
\n" ); document.write( "ans:\r
\n" ); document.write( "\n" ); document.write( "Hours all three took to finish the job=2.59 (rounded) \n" ); document.write( "
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