document.write( "Question 1145794: A, B and C can do a piece of work in 10 days. A and B can do it in 12 days, and A and C in 20 days. How many days would it take each to do the work place? \n" ); document.write( "
Algebra.Com's Answer #767072 by greenestamps(13200)\"\" \"About 
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\n" ); document.write( "You have received two responses showing typical algebraic solutions to the problem.

\n" ); document.write( "Here is an alternative solution method that makes solving problems like this involving three (or more) workers easier.

\n" ); document.write( "Consider the least common multiple of the given times. The LCM of 10, 12, and 20 is 60.

\n" ); document.write( "So look at what the given information tells us about how many of the jobs each combination of workers can do in 60 days:
\n" ); document.write( "(1) A, B, and C together could do the job 60/10 = 6 times.
\n" ); document.write( "(2) A and B together could do the job 60/12 = 5 times.
\n" ); document.write( "(3) A and C together could do the job 60/20 = 3 times.

\n" ); document.write( "Comparing (1) and (2) tells us that C alone could do the job 6-5 = 1 time in 60 days. So it takes C 60/1 = 60 days to do the job alone.

\n" ); document.write( "Comparing (1) and (3) tells us that B alone could do the job 6-3 = 3 times in 60 days. So it takes B 60/3 = 20 days to do the job alone.

\n" ); document.write( "And then A alone could do the job 6-1-3 = 2 times in 60 days. So it takes A alone 60/2 = 30 days to do the job alone.

\n" ); document.write( "ANSWERS:
\n" ); document.write( "A: 30 days
\n" ); document.write( "B: 20 days
\n" ); document.write( "C: 60 days \n" ); document.write( "
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