Math never was my strong point

My car, a 2000 Honda Civic EX, is hardly a gas hog—but when gas prices climbed over $3.00 recently I started looking at how I could get as much mileage out of a tank as possible. I’d already covered most of the suggestions, like checking for proper inflation and not carrying huge boulders in the trunk, but I knew there was one thing I could do differently—slow down. Also I tended to accelerate with a little more “enthusiasm” than was perhaps necessary.

I’ve been going fairly easy on the gas pedal, and I think I could be getting two days extra per fill-up. A tank lasts me 9 days now, when I think I used to fill up once a week. This morning on the way to work I was trying to figure out how many “free days” that translated to per year. I’m not sure if I’m just slow today, but I haven’t been able to wrap my brain around the math:

365 / 9 = 40.5 “gas tank weeks”
40.5 x 2 (2 free days per “gas tank week”) = 81

81 days “free?” That just doesn’t seem right to me. If I’m even close to that, though, it’s great!