At a speed of 60 miles per hour, a certain car uses 1 gallon of gasoline every 30 miles. If the car starts with a full 12 gallon tank of gasoline and travels for 5 hours at 60 miles per hour, the amount of gasoline used would be what fraction of a full tank?  Choose the correct choice from the following options
A) 3 / 25  B) 11 / 36  C) 7 / 12  D) 2 / 3  E) 5 / 6

Rationale: "gas used = ( 5 hours ) * ( 60 miles / hour ) * ( 1 gallon / 30 miles ) = 10 gallons portion used = ( 10 ) / 12 = 5 / 6 ans e"
Answer: E