document.write( "Question 170060: (GIVE THE ANSWER IN HOURS AND MINUTES)
\n" ); document.write( "BILL CAN BUILT A BOOKCASE IN 6 HOURS, BUT IT TAKES HIS FRIEND, DAVID, ONLY 4 HOURS TO BUILD THE SAME BOOKCASE. HOW LONG WILL IT TAKE THEM TO BUILD THE BOOKCASE IF THEY WORK TOGETHER? \n" ); document.write( "
Algebra.Com's Answer #125519 by ptaylor(2198)\"\" \"About 
You can put this solution on YOUR website!
Let x=amount of time it takes to build the bookcase when they both work together
\n" ); document.write( "So, together they work at the rate of 1/x bookcase per hour
\n" ); document.write( "Bill works at the rate of 1/6 bookcase per hour
\n" ); document.write( "David works at the rate of 1/4 bookcase per hour\r
\n" ); document.write( "\n" ); document.write( "Together they work at the rate of 1/6 + 1/4 =2/12 +3/12=
\n" ); document.write( "5/12 bookcase per hour
\n" ); document.write( "So our equation to solve is:
\n" ); document.write( "(5/12)x=1 (1 bookcase that is) multiply each side by 12
\n" ); document.write( "5x=12
\n" ); document.write( "x=12/5 = 2 2/5 hours (2/5 hour=(2/5)*60 min=24 min)
\n" ); document.write( "x=2h 24m
\n" ); document.write( "another way would be:
\n" ); document.write( "1/x = 5/12 multiply each side by 12x
\n" ); document.write( "12=5x-------same as before\r
\n" ); document.write( "\n" ); document.write( "CK
\n" ); document.write( "In 12/5 hr, Bill alone could build (12/5)*(1/6)=2/5 bookcase
\n" ); document.write( "In 12/5 hour David alone could build (12/5)*(1/4)=3/5 bookcase
\n" ); document.write( "Together they build 2/5 + 3/5 =1 bookcase\r
\n" ); document.write( "\n" ); document.write( "Hope this helps---ptaylor \n" ); document.write( "
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