Answer:
Don't really understand the question, but
<u>Solution-</u>
Fuel consumption rate = 40 miles per UK gallon (As the car is manufactured in UK)
1 UK gallon = 4.5459631 lit
1 US gallon = 3.7853060 lit


As the fuel consumption rate = 40 miles per gallon
⇒ You need 1 UK gallon of fuel to go 40 miles
⇒ You need 1.2009499 US gallon of fuel to go 40 miles
Or you can say that, to go 40 miles you need 1.2009499 US gallon of fuel
⇒ To go 1 mile you will need 
⇒ To go 738 miles you will need 0.0300237×738 = 22.1574906 US gallon of fuel
∴ 22.1574906 gallon of fuel is actually required.
∴ But, what she thinks will require is
(As she calculated using UK gallons)
3.625 = 29/8 as a fraction. Is that what you're asking?
6.6666 rounded to the nearest thousandth is 6.667.
The number in the ten thousandths place is greater than five, so the 6 in the thousandths place rounds up to a seven