The mathematics I have to go through at fuel stations that require payment in advance for a specific amount of gallons when I just want to top it off, ugh.
Each tenth of my tank is 2.4 gallons, so if I’m at 4/10 and want to top off, (10-4)=6, so 6 x 2.4 = 14.4 gallons x price of fuel per gallon which is hovering around $6.90 lately (diesel in California), so I tell the cashier person I 'd like to purchase exactly $99.36 but gosh that’s so close to $100 let’s just round it to $100.


In my wanderings around the USA I’ve only encountered one pump that allowed pump before pay. At some obscure Nevada gas station in a little pass-through town in the middle of nowhere.