So, here’s another math trick and this one may be a little less intuitive to follow. It’s about squaring numbers close to 100 without that piece of machine called the calculator.
Example: Squaring 108 i.e. Calculating (108) * (108)
Now, we know that 108 differs from 100 by a +8. We make use of this and add this 8 to the number we have.
108+8 = 116
Now, we leave 116 as the left most digits of the answer and take the square of just 8. We get 8*8 = 64.
Therefore, our answer is : 11664
And voila, your calculator agrees!
Damn, I love math tricks.