document.write( "Question 973876: If george washed a car in 20 minutes and sally washed the same car in 15 minutes how long would it take them to wash the car together? \n" ); document.write( "
Algebra.Com's Answer #595907 by josmiceli(19441)\"\" \"About 
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Add their rates of washing to get
\n" ); document.write( "their rate washing together
\n" ); document.write( "George's rate:
\n" ); document.write( "[ 1 car ] / [ 20 min ]
\n" ); document.write( "Sally's rate:
\n" ); document.write( "[ 1 car ] / [ 15 min ]
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\n" ); document.write( "Let \"+t+\" = time in minutes working together
\n" ); document.write( "\"+1%2F20+%2B+1%2F30+=+1%2Ft+\"
\n" ); document.write( "Multiply both sides by \"+60t+\"
\n" ); document.write( "\"+3t+%2B+2t+=+60+\"
\n" ); document.write( "\"+5t+=+60+\"
\n" ); document.write( "\"+t+=+12+\" min
\n" ); document.write( "It takes them 12 min working together\r
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