If gasoline costs $1.09 per gallon and alcohol costs $1.81, what fract

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If gasoline costs $1.09 per gallon and alcohol costs $1.81, what fraction of each would be used to make Gasohol 99?

(1) The mixture is predominantly gasoline.
(2) A gallon of Gasohol 99 costs $1.22.


In the original condition, the que is fraction. In a case like this, ratio is the answer, 2) is ratio in this question. Also, regard the amount of gasoline as g and the amount of alcohol as a, they become 1.09g+1.81a=1.11(g+a), in which you can figure out the relation of a and g. In a+g=1, you can figure out the answer in a unique way. Therefore, the answer is B.


 from con 1) and con 2), if one of the conditions is given by numbers and the other is given by ratio (percent,fraction), then the condition with ratio (percent,fraction) value has higher chance of being the answer.