# The ".9" in gas prices--harmless, or rip-off? **URL:** \ **Category:** Factual Questions\ **Created:** [July 24, 2002, 8:04pm UTC](https://boards.straightdope.com/t/the-9-in-gas-prices-harmless-or-rip-off/120625 "2002-07-24T20:04:08Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![ElwoodCuse](https://avatars.discourse-cdn.com/v4/letter/e/edb3f5/32.png) [@ElwoodCuse](https://boards.straightdope.com/u/ElwoodCuse)\ **Post date:** [July 24, 2002, 8:04pm UTC](https://boards.straightdope.com/t/the-9-in-gas-prices-harmless-or-rip-off/120625/1 "2002-07-24T20:04:08Z")
I did a search and didn’t turn up anything. Anyway… For as long as I can remember, gasoline prices end with a .9–three decimal places. Now, since currency only goes two decimal places, this is impossible to pay for. So why was it done? I think the obvious answer is an extrapolation of the 9s in the price of anything–to make the product appear cheaper (ie $19.99 looks better than $20). But suppose you buy exactly a gallon of gasoline, for the price of $1.299. You have to pay $1.30 for it. Does that little .001 cent add up over time into some insidiously large amount, like in, say, _Superman III_ or _Office Space_? ---
**Author:** ![zev\_steinhardt](https://avatars.discourse-cdn.com/v4/letter/z/97f17d/32.png) [@zev\_steinhardt](https://boards.straightdope.com/u/zev_steinhardt)\ **Post date:** [July 24, 2002, 8:09pm UTC](https://boards.straightdope.com/t/the-9-in-gas-prices-harmless-or-rip-off/120625/2 "2002-07-24T20:09:07Z")
> [@](#): > > \*Originally posted by ElwoodCuse \* > \*\*I did a search and didn’t turn up anything. Anyway… > > For as long as I can remember, gasoline prices end with a .9–three decimal places. Now, since currency only goes two decimal places, this is impossible to pay for. So why was it done? > > I think the obvious answer is an extrapolation of the 9s in the price of anything–to make the product appear cheaper (ie $19.99 looks better than $20). > > But suppose you buy exactly a gallon of gasoline, for the price of $1.299. You have to pay $1.30 for it. Does that little .001 cent add up over time into some insidiously large amount, like in, say, _Superman III_ or _Office Space_? \*\* Technically, there is a unit of currency called the mill, which is equivilant to 1/1000th of a dollar. It has never been minted, however. The situation would be comperable to when you want to buy a $19.99 item with a $20 bill and the seller doesn’t have change. Either you pay the $20 or you don’t get the item. Zev Steinhardt ---
**Author:** ![Church\_Key\_Kid](https://avatars.discourse-cdn.com/v4/letter/c/f9ae1b/32.png) [@Church\_Key\_Kid](https://boards.straightdope.com/u/Church_Key_Kid)\ **Post date:** [July 24, 2002, 8:11pm UTC](https://boards.straightdope.com/t/the-9-in-gas-prices-harmless-or-rip-off/120625/3 "2002-07-24T20:11:53Z")
It is set that way because the gas stations actually deal in fractions of a penny when they are buying their gas. You are not physically being ripped off (by most honest stations, anyway) because you can actually squeeze out that extra hundreth of a gallon or whatever before it rolls over to the next cent. ---
**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\ **Post date:** [July 24, 2002, 8:23pm UTC](https://boards.straightdope.com/t/the-9-in-gas-prices-harmless-or-rip-off/120625/4 "2002-07-24T20:23:05Z")
If you pump exactly 10 gallons (or better, exactly 100 gallons) in your tank, you will see that the price indicator does – or at least should – stop exactly on the penny and not roll over. If you only pump in exactly one gallon of gas, you’re too anal retentive to satisfy. ---
**Author:** ![Roadfood](https://avatars.discourse-cdn.com/v4/letter/r/9fc348/32.png) [@Roadfood](https://boards.straightdope.com/u/Roadfood)\ **Post date:** [July 24, 2002, 9:08pm UTC](https://boards.straightdope.com/t/the-9-in-gas-prices-harmless-or-rip-off/120625/5 "2002-07-24T21:08:32Z")
Some of us can remember the ancient times when gasoline prices were around 25 cents a gallon (and, I’m sure, others can remember when it was even less). A tenth of a cent as a percentage of 25 cents is significantly more than a tenth of a cent as a percentage of 125 cents. So the nine-tenths pricing really makes no sense (pun intended) anymore, it’s continued only out of historical inertia. To answer the actual question: I think you’ll find that if you tried, you wouldn’t really be able to buy EXACTLY one gallon of gas. You could buy a dollar and twenty-nine cents worth of gas, or you could buy a dollar and thirty cents worth of gas. If you went to a gas station and really REALLY insisted on getting EXACTLY one gallon, I suspect the manager would likely insist back on charging you the dollar thirty and taking the whopping tenth of a cent as pure profit. But, in general, there’s on _Superman III_ effect because the transaction isn’t based on an even gallon amount it’s based on an even dollar-and-cents amount. (Besides, the _Superman III_ effect is pure fiction anyway).