document.write( "Question 1093176: Suppose that Hortense and Mort can clean their entire house in 10 ​hours, while their​ toddler, Mimi, just by being​ around, can completely mess it up in only 6 hours. If Hortense and Mort clean house while Mimi is at her​ grandmother's, and then start cleaning up after Mimi the minute she gets​ home, how long does it take from the time Mimi gets home until the whole place is a​ shambles? It will take how many hours? \n" ); document.write( "
Algebra.Com's Answer #707805 by greenestamps(13206)\"\" \"About 
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At time 0, when Mimi arrives home, the fraction of the house that is neat is 1 (the whole house). Each hour after Mimi arrives home the fraction of the house that she messes up is 1/6; each hour that meanwhile Hortense and Mort work the fraction of the house that gets cleaned up is 1/10.

\n" ); document.write( "So after t hours, the fraction of the house that is clean is
\n" ); document.write( "\"1+-+%281%2F6%29t+%2B+%281%2F10%29t\"

\n" ); document.write( "You want to know when that fraction is 0 -- that is, when the whole house is, as you say, a shambles. So
\n" ); document.write( "\"1+-+%281%2F6%29t+%2B+%281%2F10%29t+=+0\"
\n" ); document.write( "\"%2830%2F30%29+-+%285%2F30%29t+%2B+%283%2F30%29t+=+0\"
\n" ); document.write( "\"%2830-2t%29%2F30+=+0\"
\n" ); document.write( "\"30-2t+=+0\"
\n" ); document.write( "\"30+=+2t\"
\n" ); document.write( "\"15+=+t\"

\n" ); document.write( "The whole house will be a shambles 15 hours after Mimi arrives home.

\n" ); document.write( "I have a couple of questions about this problem...
\n" ); document.write( "(1) What happens after the 15 hours? What does a negative fraction mean in this application??? Does the yard get messed up next? and then the neighbors' houses?...
\n" ); document.write( "(2) Does Mimi behave when she is at her grandmother's house?

\n" ); document.write( "just kidding....
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