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

Algebra ->  Rate-of-work-word-problems -> 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       Log On


   



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) About Me  (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) About Me  (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
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To plow 1 field at 0.536 field/hr:
(1 field)/(0.536 field/hr)=1.87 hours