Squaring Any Number Ending IN 1

• SQUARING ANY NUMBER ENDING IN 1:

Rule:  First,square the number to the left of the units digit. Then double the number to the left of the digit. Affix the units digit of this result to the square found in first step. If the result is more than 9, add the part to the left of the units digit to the square found in the first step. The units digit of the answer is always 1.

Consider the following example: Square 251.

The number to the left of the 1 is 25. we know the square of 25 is 625. Next, twice 25 is 50. affix the zero in 50 to 625.

                     625 + 5 = 630

To which are affixed the 0 and the units digit (which is always 1).

                     63,001 Answer