3.A 13.401 gal. purchase of gasoline priced at $1.399/10/gal. vs $1.40/gal.
dispenser rounding
13.401 gals. x $1.40/gal. = $18.76140 $18.76
13.401 gals. x $1.399/10/gal. = $18.747999 $18.75
Dispenser computers are not programmed to apply conventional rules for rounding (Hurlburt). Any even half-cent amount not rounded to the nearest even cent introduces a one cent increase in price. For example, a 5.000 gallon purchase of gasoline priced at $1.249/10 = $6.245000 and should be priced as $6.24, however, all motor fuel dispensers are programmed to calculate the purchase as $6.25 - a 15:10 bias for rounding up. Daily U.S. gasoline consumption of 350,000,000 gals. provides many opportunities for dispenser rounding errors at unknown cost to motorists. Dispenser computers could easily be programmed to eliminate rounding bias.
The ultimate absurdity in gasoline pricing was displayed in a photograph in the September 12, 2001 issue of the Arizona Republic on the skyrocketing prices at a local gas station in Topeka, KS following the terrorist attacks the previous day. The price-gouging operator was careful to add 9/10 cent to the $6.00 per gallon cost of his Premium Ultimate gasoline rather than a more compassionate pricing of $5.999/10 per gallon.
This industry-wide, deceptive and anachronistic pricing practice has been accepted without question by American motorists for the past 70 years!