Answer: $142
Step-by-step explanation: assume 20miles per gallon.
Then 0.05 gallon per mile.
35psi gives 30/35= 0.85 times the surface on the ground, gives square 0.85^2= 0.73 times more deflection so heatproduction a cycle or at same speed. This gives more fuelconsumption.
I once determined that when driving 50mph/80kmph constant, tires use 25% of the total fuel-consumption.
Higher speed same fuelconsumption by the tires, but more bij the higher speed. But to keep it simple only 50mph.
The fuelconsumption at 30 psi 0.05 gpm, 25% by the rolling resistance is 0.0125mpg. 35psi ,0.73 x0.0125=0.0091gpm.
The windforce stays the same 75% of total is 0.0375mpg+ 0.0091= 0.0466mpg,0.0466gpm/0.05= 93% used of fuel with 35psi then at 30 psi.
So 21000mpj x 0.05gpm= 1050 gallon
21000mpjx 0.466gpm= 979gallon.
Saving 1050-979= 71 gallonx $2= $142
Rounded here and there, and other speeds give other divisions, but to show the idea how to calculate it.
Also if 25% used is right is discussable.
