A certain car can travel 40 minutes on a gallon of gasoline at 70 miles per hour. If the car had started with a full tank and had 8 gallons of gasoline left in its tank at the end, then what percent of the tank was used to travel 80 miles at 60 mph?	Choose the correct choice
A) 15%  B) 30%  C) 25%  D) 20%  E) 40%
Let, Tank capacity = T gallon   Used Fuel = (T-8) gallons   Distance Travelled (@70 miles/hr) = 80 miles   Distance travelled in 1 gallon = Distance travelled in 40 mins (@60 miles/hr) = (70/70)*40= 
<gadget id="calculator">(70/70)*40</gadget>
<output>40</output>
40 miles   Fuel used to travel 80 miles= (80/40)= 
<gadget id="calculator">(80/40)</gadget>
<output>2</output>
2 gallon   i.e. Used fuel= (T-8) = 2 gallon   i.e. T = 10 Gallons   i.e. Used Fuel = (2/10)*100= 
<gadget id="calculator">(2/10)*100</gadget>
<output>20</output>
20%   20%
<result>D</result>
A certain car can travel 40 minutes on a gallon of gasoline at 70 miles per hour. If the car had started with a full tank and had 8 gallons of gasoline left in its tank at the end, then what percent of the tank was used to travel 80 miles at 60 mph?