On the way back,Lance could manage a steady 16mph. He placed 24 gallons of fuel in the tank ready for the round trip, thinking that this would be enough as the wagon managed to travel 8 miles per gallon.
Unfortunately, a piece of metal pierced his fuel pipe at the start of the trip and the wagon started to lose 1 gallon of fuel per hour.
Luckily he only lost fuel when moving and he lost no fuel whilst unloading his scrap metal.
Were 24 gallons enough for the round trip?