9514 1404 393
Answer:
12 liters
Step-by-step explanation:
The kerosene usage is assumed to be jointly proportional to the number of stoves and the number of hours. That is ...
v = k·s·h . . . . . for s stoves running h hours
Then the value of k is ...
k = v/(sh) = (16 L)/(12·14) = 2/21 . . . . liters per stove-hour
Then the volume of kerosene required for 7 stoves and 18 hours is ...
v = (2/21)·s·h
v = (2/21)(7)(18) = 12 . . . liters
