Step 1: Examine the Starting Point
The fuel begins at the pump located at the top of the diagram. From there, it flows down into the network of pipes. Our task is to trace the path of the fuel and determine where it goes.
Step 2: Analyze the Pipes Connected to Each Car
Each car is linked to the pump via a series of pipes. However, not all of these pipes provide a clear route for the fuel. Let’s take a look at the connections:
Car 5: The pipe leading to Car 5 is blocked by a horizontal barrier. This means the fuel can’t reach Car 5, so we can rule it out as a possibility.
Car 6: Initially, the path to Car 6 seems viable, but it’s blocked by a vertical barrier, eliminating it too.
Car 3: The pipe going to Car 3 is blocked by a horizontal section, making it impossible for fuel to get there.
Car 4: The path to Car 4 is completely unobstructed, with no barriers in the way of the fuel flow. Hence, Car 4 is the first in line to be filled.