Answer:
Step-by-step explanation:
First - if we upgrade the Car :
Current cost of fuel in car - 12000/25*2.65 = 1272$
after upgrading the car , cost of fuel in car - 12000/40*2.65 = 795$
Net saving in fuel cost - 1272-795 = 477$
Second - if we upgrade the Truck :
Current cost of fuel in truck - 12000/10*2.65 = 3180$
after upgrading the truck , cost of fuel in truck - 12000/12.5*2.65 = 2544$
Net saving in fuel cost - 3180-2544 = 636 $
So, we should upgrade the truck, because it will give more saving in fuel cost.
ANNUAL FUEL SAVINGS IN GALLONS:
CAR - 477/2.65 = 180 GALLONS
TRUCK - 636/2.65 = 240 GALLONS