If 5 machines can produce 20 units in 10 hours, how long would it take 10 to produce 80 units?  Answers
A) 63  B) 20  C) 42  D) 65  E) 84
5 machines would produce 80 units in 40 hours. Increasing the amount of machines by 2 would mean dividing 40 hours by 2.   40/2= 
<gadget id="calculator">40/2</gadget>
<output>20</output>
20   Answer : 20
<result>B</result>
If 5 machines can produce 20 units in 10 hours, how long would it take 10 to produce 80 units?