1 in 10 can do this calculation without a calculator… are you up for the challenge? (Page 2 ) | November 24, 2025

What do these challenges do for your brain?

Besides the fun aspect and the small moment of pride when we find the solution, these mini-challenges are real allies in maintaining our mental focus. They allow us to:

  • Stimulate working memory by recalling rules that were sometimes learned a long time ago.
  • Strengthens your concentration, especially when you have little time to respond.
  • Improve accuracy by avoiding haste-related errors.

It’s a bit like a quick mental workout: fast, effective and effortless!

The trap into which (almost) all of us fall

Many people read the equation, quickly do the calculations… and get the wrong answer. Why? Because they fall into the classic trap: they perform addition before multiplication. However, in mathematics,   the order of operations   is crucial. This famous rule, often called PEMDAS or BODMAS, specifies that multiplication always comes before addition.

So here’s the correct approach:

  1. Let’s start with multiplication:
    • 2 × 1 = 2
    • 6 × 6 = 36
  2. So let’s add the results: