Imagine being asked to find the square (multiply a number by itself) of a number ending in 5. eg (35×35,95×95)
This little trick will help you find the answer in fewer than 3 seconds.
Let us use 65 for example
1.Take the digit(s) preceding 5 and multiply it by the next highest number.
So the answer will be 42xx
2. Put 25 at the end of the number you have (the 2 xx at the right) . It twill always end in 25
View the bellow examples including how this method can be used for 3 digit numbers as well