Ekādhikena Pūrvena means: “By one more than the previous one”

• Squares of numbers ending with 5 :

We relate the sutra to the ‘squaring of the numbers ending with 5’.

Consider the example, 25. Here the number is 25. We have to find out the square of the number. For the number 25, the last digit is 5 and the 'previous' digit is 2. Hence, 'one more than the previous one', that is, 2+1=3. The Sutra, in this context, gives the procedure 'to multiply the previous digit 2 by one more than itself, that is, by 3'. It becomes the L.H.S (left hand side) of the result, that is, 2 X 3 = 6. The R.H.S (right hand side) of the result is 5² , that is, 25.

Thus, (25)² = 2 X 3 / 25 = 625.

Apply the formula to find the squares of the numbers 15, 45, 85, 125,etc.