tax math

Today I tracked down a map of Tucson's city limits (pdf) because there's this one mall on the northwest side of town that's not in them, and the sales tax there is the straight 5% Arizona sales tax. I was reminded of this fact when I noticed that I paid 8.1% on the printer we got yesterday. I needed the map to learn that there are no shopping centers on my side of town that are not in the city limits.

Now I have to do some math: 3% of a $70 (on sale) printer is $2.10. If it's about 22 miles one way to get to the far mall, and I hit all the stoplights on the way so I only get 22 mpg, I'd use two gallons of gas at $2.59 per gallon (this week), so that wouldn't be worth it.

To make it worth it, I would need to spend at least, um, 0.03x = 2G, where G = the price of gasoline, so being accurate and using 0.031, x = $167.097.

Hahahahahahahahahahaha!

[It's my blog, so I can laugh at significant digit jokes if I want.]

Anyway, I don't know my actual cross-town gas mileage or the price of gas next week, so I'm comfortable saying x is about $200. The only things I've bought recently that cost more than $200 were a lot of kapok and a sewing machine, neither of which are readily available at that mall, so I think I'll just stay on my side of town and pay taxes for construction on roads I don't use very much.