You can put this solution on YOUR website! .
If it takes 1 man 2 hours to work, how long would it take 4 men working at the same rate?
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Usually the problems similar to this, go in more precise formulation (and, actually, require more precise formulation):
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"If it takes 2 hours for one man to complete a job, how long would it take for four men working at the same rate?
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Obvious, it will take four times less time: = hour.
