Question 479775
paul can mow the grass in 50 minutes, but it takes Dan three timese longer. how long will it take them to mow the grass if they worked together?
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Paul does 1/50 of the job per minute.
3 times longer is 150 minutes longer = 200 minutes
Dan does 1/200 per minute.
Together, they do 1/50 + 1/200 per minte = 1/40 per minute
--> 40 minutes