Find out the square of 89?

Option 4 : 7921

**Given:**

The given number = 89

**Concept:**

Calculation skills trick

**Calculation:**

**Step - 1**

Write down the squares of each of the digits in two digit format i.e. 8^{2} = 64 and 9^{2} = 81

The number obtained after this step is 6481**.**

**Step – 2**

Multiply the digits with each other and also with the power 2 i.e. 8 × 9 × 2 = 144

**Step – 3**

Add the number obtained in **step - 2** with the number obtained in **step – 3 **keeping the unit place empty i.e.

6 4 8 1

1 4 4 _

**7 9 2 1 **

This is our final answer.