The Doors

by Serhiy Grabarchuk Jr

Solution Step 0/0

The floor plan of a house has 8 rooms and 12 doors as is shown. Doors A and B lead outside.

Each door in the house opens in only one direction on its hinge and when fully opened is 90 degrees from its closed position.

Given that it is possible to fully open all the doors in the house without any door getting in another door’s way, can you determine which one of the two lettered doors opens inward and which one outward?

Note! A door is slightly wider than half of a room’s side, so that doors at the opposite sides of a room pointing in the same direction can get in each other’s way when opened towards each other – as is shown in the lower right corner.


The only way when all the doors can be fully opened is when the door A opens inward and the door B – outward, as is shown in the illustration.

Check A - inward, B - inward
Check A - inward, B - outward
Check A - outward, B - outward
Check A - outward, B - inward