Puzzle - Rate
I travelled from London to Glasgow last week at 60 miles per hour, I had filled my petrol tank just before I left, so it was full with 25 gallons.
Unfortunately, my petrol tank sprang a leak immediately and I only managed to drive 300 miles before I ran out of petrol.
My car does 30 miles per gallon, how fast was I losing petrol through the hole?
[Ref: ZFAU] © Kevin Stone