Question

How to find the square of a number lying between 25 to 50 ?

Answer 1

Let's solve ${49}^2$ as an example
First, take the difference of 49 and 25 = 24
Then take the difference of 49 and 50 = 1 and square it we get 1
Hence, first two digits = 24
last two digits =01 (you cannot take only one, since we need two digits)
Hence square of 49 = 24 01 (answer)