Problema Solution
with the old combined, nikita's entire wheat crop can be harvested in 72 hr, but a new combined can do the same job in 48 hr. how many hours would it take to harvest the crop with both combines operating?
Answer provided by our tutors
The rate of the old combined is: 1/72 wheat crop per hour
The rate of the new combined is: 1/45 wheat crop per hour
Let 't' represent the time in hours needed to harvest the crop with when both machines are working.
t(1/72) + t(1/48) = 1
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click here to see the equation solved for t
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t = 28.8 hours
It will take 28.8 hours to harvest the crop with both combines operating.