Question 127036
You are mixing gasoline and alcohol
(cost of a gallon of gasahol) =
(price per 1 gallon of gasoline)x(fraction of a gallon used)
+(price per 1 gallon of alcohol)x(fraction of a gallon used)
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If {{{p}}}% of gasoline is used, the fraction of 1 gallon
would be {{{p/100}}}
The fraction of alcohol used would then be {{{1 - (p/100)}}}
The formula for the cost per gallon of gasahol is:
{{{C = g*(p/100) + a*(1 - p/100)}}} answer
suppose I had:
g = $3 /gal
a = $4 /gal
p = 90
{{{C = 3*(90/100) + 4*(1 - 90/100)}}}
{{{C = 3*.9 + 4*.1}}}
{{{C = 2.7 + .4}}}
{{{C = 3.1}}}dollars /gal gasahol