At first glance, this math puzzle looks almost too easy to be interesting.

The numbers are familiar. The operations are basic. There are no complicated fractions, square roots, or enormous numbers.

Yet thousands of people can arrive at different answers when they see the same expression:

50 + 50 − 25 × 0 + 2 + 2 = ?

The image even comes with a challenge: don’t use a calculator—use your brain.

That little instruction is enough to make the puzzle surprisingly tempting. You may look at the equation and immediately think you know the answer. But before checking anyone else’s response, take a moment and solve it yourself.

What did you get?

90?

79?

104?

Or perhaps something completely different?

The interesting part isn’t just the final number. The real lesson is about order of operations, a basic mathematical convention that tells us which calculations should be performed first.

And once you understand that rule, the puzzle becomes much easier.

Let’s take it step by step.

The expression is:

50 + 50 − 25 × 0 + 2 + 2

The first thing many people do is simply work from left to right.

If you do that, you might calculate:

50 + 50 = 100

Then subtract 25:

100 − 25 = 75

Then multiply by zero:

75 × 0 = 0

Then add 2 and 2:

0 + 2 + 2 = 4

That approach produces 4.

It feels logical because we often read from left to right.

But there’s a problem.

In standard arithmetic, multiplication is performed before addition and subtraction.

That means you cannot simply calculate everything from left to right.

The multiplication part must be handled first.

Look carefully at the expression:

50 + 50 − 25 × 0 + 2 + 2

The multiplication is:

25 × 0

And anything multiplied by zero equals zero.

So:

25 × 0 = 0

Now the equation becomes:

50 + 50 − 0 + 2 + 2

At this point, there are no multiplications left.

Now we can work through the remaining addition and subtraction from left to right:

50 + 50 = 100

100 − 0 = 100

100 + 2 = 102

102 + 2 = 104

So the standard answer is:

104

And that’s exactly where the puzzle becomes interesting.

The zero doesn’t make the entire expression disappear.

It only makes 25 × 0 equal to zero.

The 50 + 50 remains.

The two additional 2s remain.

So the final result is 104.

Why do so many people get these puzzles wrong?

One reason is that the human brain naturally wants to process information in the order it appears.

When you see:

50 + 50 − 25 × 0 + 2 + 2

your eyes move from left to right.

Your brain may instinctively begin calculating as it goes.

But mathematics has a hierarchy.

Certain operations have priority over others.

This is commonly remembered through the acronym PEMDAS:

Parentheses

Exponents

Multiplication

Division

Addition

Subtraction

Another commonly used version is BODMAS, which refers to brackets, orders, division, multiplication, addition, and subtraction.

The terminology may vary depending on where you learned mathematics, but the essential idea is the same.

Multiplication and division generally take priority over addition and subtraction.

That means the multiplication in this puzzle must be handled before the surrounding addition and subtraction.