Problem Solving – 15 Door Puzzle
15 Door Puzzle – You must shut all the doors on the ground floor of the castle without going through any door twice. It is a bit harder than it seems.
Classroom Problem Solving
15 Door Puzzle
Here’s a challenging puzzle to use as a classroom poster or a fun addition to homework.
The ground floor of this castle has 15 doors. Each night before bed you must shut all the doors without going through any door twice. You may start either inside or the outside and once you pass through a doorway it is considered shut.
There are many ways to solve this puzzle. See how many you can find.
Things to Think About & Test Out:
– Should I start on the outside?
– Should I start on the inside?
– Should I start in a room with an even number of doors?
– Should I start in a room with an odd number of doors?
– How will I record where I’ve been? Do some people place a counter over each door they’ve traveled through? Might this work for you? Think of a ‘better’ way to record your path?
– Think about how to use the numbers above the door to record your path?
– How will you record the room you started in? How will you record if you started on the outside of the puzzle?
– Since there are many ways to solve this puzzle some people have written a letter on the floor of each room and then the number sequence of doors they go through to solve the puzzle. Test this idea out and see if this works for you.
Notes from the Publisher:
– I have often wondered if it is possible to start in one room, close all doors and finish in the room I started in i.e. can you start in your bedroom, shut all the doors and finish back in your bedroom. After a long time trying I am yet to find a way. Give it a try and see if you have better luck.
– I have also thought about this house being located in a rainy country. If it was me, when it was dark, cold, and wet I would not want to travel long distances outside the building i.e I would try to avoid running outdoor 5 and indoor 15.
Are there solutions where the person spends a shorter time outside?
Wall Display Ideas:
Task Card Versions:
Included in This Download: