[Christ]

What's so difficult about 5,000/26 as opposed to .038*5,000?

You're doing the same math.

To simplify the math, you can change your mileage estimate to 5,200 and divide that by 26. Nobody knows for sure exactly how many miles they're going to travel per year anyway, so it's just as valid to make your mileage a multiple of your average MPG and figure it from there as it would be to attempt to figure it out any other way.

5,200/26 = 200. Man, that was hard.

You could also change your MPG figure to 25, and get the same result:

5,000/25 = 200.

.038*5,000.... umm... yep, need a calculator for that. But, for the sake of argument, we can simplify the problem to it's actual equation, then figure it from there:

.038*5,000 =
.38*500 =
3.8*50 =
38*5 =
190

The other way to solve the equation would have involved division, which many people simply cannot do in their heads.

So we were off by 10 gallons using the old way vs your way... and we were even 10 gallons high. At $4 per gallon, that's $40 for the year. Surely not insignificant, but I've always been taught to budget for more than I think I'll need anyway.

Guess you defeated your own point there, eh?