The fuel tank of an automobile had a capacity of 14.8 gallons. If the density of gasoline is 42.0 ib/ft^3?

Question

What is the mass of fuel in kilograms when the tank is full?

Answer 1

The previous poster put in his own density for gasoline (a rather high one at that) instead of the 42 pounds per cubic foot (=0.67 kg/l) you stated. And he seems to be the UK and using an Imperial gallon.

For the US:

42 lb/gal / 7.48 US gal/cu ft = a density of 5.61 pounds per gallon. (note that is really light or really hot gasoline!)

14.8 US gallons x 5.61 pounds/ US gallon = 83.1 pounds

83.1 pounds / 2.2 pound/kg = 37.8 kg.

For the UK/former Empire: 45.2 kg if you are using Imperial gallons.

Answer 2

Assume
gallon=4.55lit
density=.8kg/dm^3=8kg/lit
The unit you are using for density
is not clear to me. Hence the above.
14.8 gallons=14.8*4.55 lit
mass=14.8*4,55*.8 kg=53.872 kg