Taken from: MGMAT CAT, I didn't quite understand their explanation.
Bob just filled his car's gas tank with 20 gallons of gasohol, a mixture consisting of 5% ethanol and 95% gasoline. If his car runs best on a mixture consisting of 10% ethanol and 90% gasoline, how many gallons of ethanol must he add into the gas tank for his car to achieve optimum performance?
9/10
1
10/9
20/19
2
ANS:[spoiler]10/9[/spoiler]
Bob just filled his car's gas tank with 20 gallons of gasohol, a mixture consisting of 5% ethanol and 95% gasoline. If his car runs best on a mixture consisting of 10% ethanol and 90% gasoline, how many gallons of ethanol must he add into the gas tank for his car to achieve optimum performance?
9/10
1
10/9
20/19
2
ANS:[spoiler]10/9[/spoiler]
