Squaring Fives

Want to know how to square any number that ends in 5?

Okay!

Two things to do this.

First, the answer will always end in 25.

Next, you need to take number before the 5 in the number being squared, and multiply it by the next higher integer.

Then, put that number in front of “25” and you have your answer.

Examples:

What is 35 squared?

Well, the answer will end in 25, and it will begin with 3 (the number before 5 of the number being squared) x 4 (one integer higher than our 3).

The answer is 1,225.

55 squared?

(5 x 6) 25 , or 3,025.

115 squared?

(11 x 12) 25, or 13,225.

3,535 squared?

(353 x 354) 25, or 12,496,225, though at this stage it’s probably easier just to reach for a calculator.

Awesome nonetheless!