Question 1117873
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You have two good solutions from other tutors using the traditional algebraic approach to this kind of problem.<br>
Here is an alternative method for solving this kind of problem that many students find easier.<br>
One crew takes 200 hours to do the job; the other takes 300 hours.<br>
Consider the least common multiple of the two times; in this problem, 600 hours.<br>
In 600 hours the first crew could complete 3 of these jobs; in 600 hours the second crew could complete 2 of them.<br>
So together in 600 hours the two crews together could complete 5 of the jobs.<br>
Then, to complete just the one job, the two crews would need to work for 600/5 = 120 hours.