- Thread starter Damb.
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After traveling for a distance the water tank is half full and 1/2 a tank of full was consumed. If the water tank was empty the fuel consumed would have been 1/6 of a tank. What kind or relationship can you get from this? Do you need additional variables?

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Hi Damb. We're instructed to ignore the fuel tank weight.So there has to be a constant value which is the weight of the actual tank …

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The distance is changing as the truck moves so I am not sure about the distance being constant. However the distance in the two scenarios are the same.I originally assumed that you don’t need to worry about the distance that the truck travels because it remains constant, is this true?

(0.75x is the average amount of water over the trip for the first scenario).

But this is what ive been trying to work with the whole time and I feel like it is not the direction you are trying to hint me towards

therefore f = k (litres of water in the tank + litres of fuel in the tank)

therefore when there is no water in the tank the fuel consumption = 1/6 of the fuel in the tank

therefore k must be equal to 1/6

therefore when fuel consumption is half of the tank f = (1/6)*(3/4)*litres of water in the tank + (1/6)*(3/4)*litres of fuel in the tank

then f = (1/8)*(litres of water in the tank + litres of fuel in the tank)

then f - (1/8)*litres of fuel in the tank = (1/8)*litres of water in the tank

as f = (1/2) litres of the tank, then (3/8)* litres of fuel in the tank = (1/8)*litres of water in the tank

therefore 3*litres of fuel in the tank = litres of water in the tank

so tat is obviously wrong but could it be the inverse? 1/3 of the fuel tank will be left?