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You can put this solution on YOUR website!
\n" ); document.write( "As tutor @ikleyn indicates, you get more brain exercise, and better problem-solving experience, solving the problem using logical reasoning and simple calculations instead of formal mathematics.
\n" ); document.write( "Here is another informal path to a solution of the problem.
\n" ); document.write( "The job would have taken 20 days if he used 2 tractors for the whole time.
\n" ); document.write( "He used the 2 tractors for only 8 days.
\n" ); document.write( "After those 8 days, there would have been 12 days left if he had continued to use only 2 tractors.
\n" ); document.write( "But after those first 8 days he started using 2+6 = 8 tractors instead of 2.
\n" ); document.write( "Since he now has 4 times as many tractors, the number of days needed to complete the job gets cut by a factor of 4: the 12 days becomes 12/4 = 3 days.
\n" ); document.write( "ANSWER: 3 days
\n" ); document.write( "NOTE:
\n" ); document.write( "Many (most) people will say I'm too much of a stickler for proper language.... But upon reading this problem the first time I was curious how \"A farmer\" could use 2 tractors to do a job -- much less how he could use 8 of them....
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