The 1089 Number Trick (Reverse & Subtract)

This is a famous and always-working math trick called the 1089 trick.

✨ Step-by-Step Trick


1️⃣ Take any 3-digit number

👉 Condition:

First and last digits must be different

Example: 532

2️⃣ Reverse the number

532 → 235

3️⃣ Subtract the smaller from the bigger

532 − 235 = 297

4️⃣ Reverse the result

297 → 792

5️⃣ Add both numbers

297 + 792 = 1089 🎉

👉 Answer is ALWAYS 1089


🤔 Why Does This Always Work? (Simple Explanation)

Let the number be ABC

A = hundreds digit

B = tens digit

C = units digit

Original number = 100A + 10B + C

Reverse number = 100C + 10B + A

Subtraction:

 => (100A + 10B + C ) - (100C + 10B + A) 

=> 99 (A - C)

So the result is always a multiple of 99

Examples:

99 × 1 = 099

99 × 2 = 198

99 × 3 = 297

99 × 4 = 396

...

Now when you reverse and add any of these:

396 + 693 = 1089 

Always 1089

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