Many people get this exercise wrong. Can you find the right answer? The solution is in the comments below 👇

 

In summary: this is why many people are mistaken on this issue.

This calculation seems very simple at first glance, but it traps a lot of people. The error doesn't come from the calculation itself, but from a mathematical rule that many have forgotten. And there's a good chance your brain will fall into the trap too.

At first glance, this calculation seems very simple. You might think you could solve it in a few seconds, without even setting up the problem. And yet, a great many people get the answer wrong. It's not because they can't count, far from it. In reality, the error almost always stems from a mathematical rule that many have forgotten over time. And you'll see that your brain is probably playing a little trick on you.

Why does this calculation trap so many people?

Here is the operation in question:

50 + 50 − 25 × 0 + 2

Most people naturally start calculating from left to right. This makes sense, since that's how we read. So many people do:

50 + 50 = 100
100 − 25 = 75
75 × 0 = 0
0 + 2 = 2

And they find 2.
Others make a slight variation and find 0.

But these answers are wrong. And it's not a question of intelligence, it's simply a natural reflex: our brain likes to go in order, without thinking about mathematical rules.

The rule that many have forgotten

In mathematics, there is a specific order for performing operations. This rule is learned in school, but many people forget it over the years.

The rule is simple:

Multiplication and division first,
then addition and subtraction

This rule is often called: "multiplication before addition".

This means that in our calculation, we should not start with 50 + 50.
We must first do 25 × 0.

Let's do the calculation again correctly

We repeat the operation, respecting the rule:

50 + 50 − 25 × 0 + 2

We begin with multiplication:

25 × 0 = 0

The operation therefore becomes:

50 + 50 − 0 + 2

Now, we calculate from left to right:

50 + 50 = 100
100 − 0 = 100
100 + 2 = 102

The correct answer is therefore 102.

Why our brain is almost always wrong

There's a very simple reason for this common mistake: our brain loves shortcuts. It looks for the fastest solution, not necessarily the most correct one.

When we see a sequence of numbers, our brain wants to go from left to right because it's simpler and faster. Thinking about the order of operations requires a little extra effort, and in everyday life, we often operate on autopilot.

That's exactly why this type of calculation goes viral on the internet: it traps our instinctive way of thinking.

A little tip to never make a mistake again

There is a very simple trick to remember the order of operations:
Always think: multiplication and division first, addition and subtraction last.

If you see a calculation with several different operations, first look for the multiplications and divisions. Do them first, and only then do the rest from left to right.

It's a small habit to get into, but it avoids a lot of mistakes, even on simple calculations.

Key takeaways

This mathematical trap mainly shows one interesting thing: sometimes it is not the difficulty that makes us make mistakes, but haste.

We think it's easy, so we go too fast, and that's where we make a mistake.

This shows that even a primary school level operation can trap thousands of adults simply because a basic rule is forgotten.

Sometimes the right answer is not the fastest, but the one you take the time to check.