document.write( "Question 109808This question is from textbook
\n" ); document.write( ": Beatrice and javier can paint a room in 5 hours. Working alone, javier can paint the room in 2 hours less time than Beatrice can. Find how long it takes her to paint the room alone.
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Algebra.Com's Answer #80014 by edjones(8007)\"\" \"About 
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Let b= hours for Beatrice to paint the room. j= hrs for Javier to paint room.
\n" ); document.write( "j=b-2
\n" ); document.write( "The trick of these problems is to take the reciprocals of the hours to do the job. The reciprocal tells us what fraction of the job can be done in 1 hour.
\n" ); document.write( "1/b + 1/j = 1/5
\n" ); document.write( "1/b + 1/(b-2)=1/5 Replace j with b-2
\n" ); document.write( "5(b-2)+5b=b^2-2b multiply both sides by 5b(b-2) to eliminate fractions.
\n" ); document.write( "5b-10+5b=b^2-2b
\n" ); document.write( "-b^2+2b+5b+5b-10=0
\n" ); document.write( "-b^2+12b-10=0
\n" ); document.write( "b^2-12b+10=0 multiply each side by -1.
\n" ); document.write( "b=.9 too low to be an answer.
\n" ); document.write( "b=11.1 hrs approx Answer.
\n" ); document.write( "j=9.1 hrs approx
\n" ); document.write( "Check:
\n" ); document.write( "1/9.1 + 1/11.1 = 1/5 approx
\n" ); document.write( "Ed \n" ); document.write( "
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