Can you solve this test without a calculator?

The order of operations, that unsung hero of our daily lives

Remember: starting in middle school, we learn the famous order of operations. It has different names depending on the country (PEMDAS, BODMAS…), but the principle remains the same:

  • Parentheses
  • Exponents (or powers)
  • Multiplication and division, from left to right
  • Additions and subtractions, also from left to right

Don’t panic, here we only have three operations to manage: multiplication, subtraction, and addition. But it is precisely this  deceptive simplicity  that makes the exercise misleading.

Let’s solve it together, step by step.

Let’s take our time. Here’s the procedure:

11 – 11 × 11 + 11

We begin with multiplication:
11 × 11 = 121

The calculation therefore becomes:
11 – 121 + 11

Next, we solve the remaining operations from left to right:
11 – 121 = -110

Then,
-110 + 11 = -99

The result

 

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