Why do gasoline costs end in 9/10 cents?

Please explain simply why gasoline costs end in 9/10 cents since there is no such thing as 9/10 cents?
Asked Jan 14, 2010
It's a stupid ploy to make people think they're saving money when they're not. It's just a big scam. People go, "Well I can either pay 20.00 a gallon, or 19.99 a gallon" Even though it's really 19.99(9/10) a gallon.
Answered Jan 14, 2010
Edited Jan 14, 2010

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