Question

What is the square root of 36?

• A. 2
• B. 3
• C. 5
• D. 6

Answer 1

The correct option is D

6

We know that sum of consecutive odd numbers give a square number. So, if we keep subtracting consecutive odd numbers from the given square number, we will eventually get 0. The number of steps taken to get 0 is equal to the square root of the given number.

Step 1 $\Rightarrow$ 36 - 1 = 35

Step 2 $\Rightarrow$ 35 - 3 = 32

Step 3 $\Rightarrow$ 32 - 5 = 27

Step 4 $\Rightarrow$ 27 - 7 = 20

Step 5 $\Rightarrow$ 20 - 9 = 11

Step 6 $\Rightarrow$ 11 - 11 = 0

It took 6 steps.
So, square root of 36 is 6.

Note: This method is not advised for larger numbers.