Factor Tree Puzzles Inspired by Dr. Harold Reiter

Yesterday, I shared about all the amazing things I learned/experienced as part of the Tulsa Math Teachers’ Circle Summer Immersion Workshop. As part of that post, I mentioned that I had created some factor tree puzzles after being inspired by the puzzles shared by Dr. Harold Reiter and the puzzle created by one of the other participants.

These puzzles involve a factor tree in which each terminating leg of the tree represents a prime number. Each variable represents a unique digit. So, if a is equal to five, then b cannot be equal to five.

I really enjoyed solving the puzzle created by another teacher in our group, so I decided I should try my hand at creating my own puzzles. 

Here are the four puzzles I ended up creating myself. In all honesty, I created way more than four puzzles. But, many of the puzzles I created turned out to have multiple solutions or mistakes. These four puzzles have been verified by both my husband and myself to have only one solution.

I decided to place circles around the prime numbers to further clarify the puzzles. 

The difficulty level definitely increases as the puzzle number increases. Puzzle 1 is the easiest. Puzzles 2 and 3 are trickier. And, Puzzle 4 is a beast. It took two people with math degrees a very long time to verify that there was one solution. So, I would NOT recommend giving puzzle 4 to students. Unless of course, there’s some logical step that makes solving it much easier than the route my husband and I ended up taking!