If Jenny’s car gets 26 mpg with regular unleaded, and Tommy’s car gets 18 mpg on ethanol, and Johnny’s car gets 24 mpg on natural gas, and the cost of gasoline is $1.96 per gallon and the price of ethanol is . . .
America’s math future or everyday life in Brazil?
SAO PAULO, Brazil — Here’s an alternative fuels word problem that might baffle even the best U.S. math students:
Jose drives his black flex-fuel Toyota Corolla into a Esso station on Rua Henrique Schaumann, a busy thoroughfare in Sao Paulo. He sees that gas costs 2.60 Brazilian reais per liter and ethanol costs 1.55 reais per liter. If Jose wants to get the most mileage for his money, which fuel should he choose?
But for Brazilians, especially the millions who drive flex-fuel cars that run on any mixture of gasoline and ethanol, that question is a breeze.
“Here’s the rule of thumb,” said Jose himself, full name Jose De Luca, a 30-year-old industrial engineer. “When the price is 70 percent or less the price of gas, it’s worth using ethanol.”
He’s got the right idea, says Adriano Pires, an economist and director of the energy consulting firm Centro Brasileiro de Infra Estrutura. According to Pires, the 70 percent figure is generally accepted as correct, although it can vary slightly depending on a car’s make and model.
And lets add in the Pickens plan just for giggles:
“The natural gas calculation is different,” Jose De Luca said. “The way it was explained to me, you have to drive a lot — 80 or 100 kilometers a day — for it to be worth the initial investment.”