posted by elisabeth .
The density of gasoline is 730 kg/m^3 at 0'C. One gallon of gasoline occupies .0038 m^3. Gasoline's volume expansion coefficient is .00096'C ^-1.
How many kilograms of gasoline are obtained when 9 gallons of gasoline are bought @ 0'C rather than 18"c (temp. at the filling station)?
answer in kg???
Multiply 9 gallons by (1 + 18C*.00096'C ^-1) That is the number of gallons you would have if the temperature were raised back to 18 C.
Next, you need to convert that number of gallons to m^3 and multiply by the density at 18 C, which that have given you in kg/m^3.
What they are really interested in, I believe, the number of EXTRA kg you get by pumping at the lower temperature.
Basically, you get 1.73% more, which comes from the 18C*.00096'C ^-1 thermal expansion term