At first glance, this looks like a simple math problem. No calculator, no tricks… or is there?

The challenge:

4 + 4 + 4 + 4 + 5 × 0! = ?

Most people rush to add the fours together and forget one tiny mathematical rule that completely changes the answer.

Before you scroll any further, take a moment and solve it yourself.

👇 What’s your answer? Write it in the comments first!

✅ Answer

The key is remembering the order of operations:

1. Factorial first:
   0! = 1 (By definition, the factorial of zero is always 1.)
2. Multiplication next:
   5 × 1 = 5
3. Addition:
   4 + 4 + 4 + 4 + 5 = 21

🎉 Correct answer: 21

Did you get it right, or did the 0! catch you by surprise? 😄