Bunuel
Official Solution:
At 12:00 in the afternoon, Paul left his home with a full 50-liter tank in his car. He had driven 75 miles when the tank developed a leak and the car started to lose \(\frac{1}{5}\) liters of fuel per minute. If Paul is traveling at a constant speed of 50 miles per hour and his car consumes 10 liters for every 100 miles, at what time of the day will Paul run out of gas?
A. 4:00 PM
B. 4:15 PM
C. 4:30 PM
D. 5:00 PM
E. 5:20 PM
Given that Paul's speed was 50 miles per hour, the tank began to leak \(\frac{75}{50}=1.5\) hours after he left home, which was at 1:30 PM. At this time, the tank contained \(50 - 10*0.75 = 42.5\) liters of fuel. From that point forward, the car was losing a total of 17 liters per hour: \(\frac{60}{5} = 12\) liters due to the leak and \(\frac{50}{100}*10 = 5\) liters for engine operation. Consequently, after 1:30 PM the fuel would only last for \(\frac{42.5}{17} = 2.5\) hours. Therefore, Paul will run out of gas at \(1:30 + 2:30 = 4:00\) PM.
Answer: A
Hi Bunuel, can you please help me understand how did you arrive at the highlighted part of the solution. Thanks in advance!
The highlighted part explains the combined fuel loss after the leak starts at 1:30 PM: