document.write( "Question 186549: If sally can paint a house in 4 hours and John can paint the same house in 6 hours, how long will it take for both of them to paint the house?\r
\n" ); document.write( "\n" ); document.write( "Solution:\r
\n" ); document.write( "\n" ); document.write( "Sally's speed of painting the house is 1/4 per hour. John's speed is 1/6 per hour.
\n" ); document.write( "Let T = time.
\n" ); document.write( "1/4 T +1/6 T =1
\n" ); document.write( "(1/4+1/6)T=1
\n" ); document.write( "(3/12+_2/12) T=1
\n" ); document.write( " 5/12 T=1
\n" ); document.write( " T=12/5=2 2/5
\n" ); document.write( "T=2hours 12 minutes.
\n" ); document.write( "Answer: Sally and John can paint the house in 2 hours and 12 minutes. \n" ); document.write( "
Algebra.Com's Answer #139788 by irkagorska(1)\"\" \"About 
You can put this solution on YOUR website!
We can use the formula: rate x time = 1(job done)
\n" ); document.write( " Let T be the time needed for both to paint the house
\n" ); document.write( " Sally's rate is 1/4 per hour
\n" ); document.write( " John's rate is 1/6 per hour
\n" ); document.write( " So : (1/4)T +(1/6)T=1
\n" ); document.write( " (3/12+2/12)T=1
\n" ); document.write( " (5/12)T=1
\n" ); document.write( " T=12/5
\n" ); document.write( " 12/5 hrs=2hours and 12 minutes.
\n" ); document.write( " \n" ); document.write( "
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