The Math PhD’s Secret Trick: Is the Answer 120 or 5!? Have you ever come across a simple math puzzle that starts an argument in the comments? This one looks straightforward, but a clever little detail makes it much more interesting. The equation is 230 − 220 ÷ 2 = ? One person says the answer is 120, while a Math PhD confidently gives the answer as 5! So, who is right?

To solve the original equation, we need to follow the standard order of operations, known as PEMDAS or BODMAS. Division comes before subtraction, so we first calculate 220 ÷ 2 = 110. Then we subtract that result from 230: 230 − 110 = 120. That means the first person is absolutely correct!

But the Math PhD isn’t wrong either. The secret is the exclamation mark after the number 5. In mathematics, this symbol represents a factorial, not just excitement. A factorial means multiplying a number by every positive whole number below it until reaching 1. So, 5! = 5 × 4 × 3 × 2 × 1.

Let’s calculate it: 5 × 4 = 20, then 20 × 3 = 60, then 60 × 2 = 120, and finally 120 × 1 = 120. That’s exactly the same result as the original equation! 🎯 Both answers are correct: one is written as a regular number, while the other uses factorial notation. Sometimes the smallest symbol makes the biggest difference!