An Unusual Matchstick Puzzle Has Surfaced Online

• 3.11.2026, 13:28

Try to come up with an unexpected solution.

Can the sum of two positive numbers be less than either of them? In standard arithmetic, this is impossible, but this is exactly the kind of mistake that appeared in a new matchstick puzzle.

The puzzle was published by a Japanese website Nōtore Biyori.

You are not allowed to add new matches or remove existing ones. All numbers and mathematical symbols must be in the correct form after the move.

The problem may seem difficult because of the significant difference between the correct and incorrect answers.

However, matchstick puzzles aren’t always solved by changing the result of the calculation.

Mathematical symbols also play an important role in such examples.

After all, the “plus” sign consists of only two matches arranged perpendicular to each other. Changing its shape can affect the entire equation.

However, simply transforming the sign is not enough. You need to find an arrangement of matches such that the numbers also form a correct expression.

It is precisely the combination of these two conditions that makes the puzzle interesting.

Which match will correct the incorrect equation without changing the total number of matches?

Correct answer

To solve the puzzle, you need to change the plus sign and the first digit of the equation.

First, remove the vertical matchstick from the “plus” sign between the numbers 51 and 50.

After that, a horizontal matchstick will remain from the “plus” sign, forming a “minus” sign.

Move the removed matchstick to the number 51.

Place it vertically in the upper right part of the digit 5.

This will turn the 5 into a 9, and the number 51 will become 91.

After this single move, we get:

91 − 50 = 41

Now the equation is correct.

If you subtract fifty from ninety-one, the result is indeed forty-one.

So, a single match allowed us to change both the mathematical sign and the first digit of the equation at the same time.

At the same time, the number 50 and the result 41 remained unchanged.