SOLUTION: if 1 tractor ploughs a field in 5.6 hours and another can plough the same field in 2.8 hours. How long would it take if both were working simultaneously to plough the field

Question 980744: if 1 tractor ploughs a field in 5.6 hours and another can plough the same field in 2.8 hours. How long would it take if both were working simultaneously to plough the field
Found 2 solutions by Alan3354, macston:
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
if 1 tractor ploughs a field in 5.6 hours and another can plough the same field in 2.8 hours. How long would it take if both were working simultaneously to plough the field
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2.8 is 1/2 of 5.6, equivalent to 2 tractors that take 5.6 hours.
--> 5.6/3 hours together.

Answer by macston(5194) (Show Source): You can put this solution on YOUR website!
.
Tractor 1: (1 field)/(5.6hrs)=0.179 field/hr
Tractor 2: (1 field)/(2.8hrs)=0.357 field/hr
Together: 0.179 field/hr+0.357 field/hr=0.536 field/hr
.
To plow 1 field at 0.536 field/hr:
(1 field)/(0.536 field/hr)=1.87 hours

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