Off Topic · How to pretend you are smart (page 1)

First of all, 5 x 5 =25. Everyone should know this.
This matters because 25 will always be appended to squares of numbers that end in 5.

For example:
15 x 15 = “1 x 2” + “25” = 225
25 x 25 = “2 x 3” + “25” = 625
35 x 35 = “3 x 4” + “25” = 1225

See the pattern?
Take the first number in the digit, and multiply it by the plus+1 of itself. Then append 25.

Another example:
45 x 45 = “4 x 5” + “25”
45 x 45 = “20” + “25”
45 x 45 = 2,025

Try it with a bigger number… formula still works…
125 x 125 = “12 x 13” + “25”
125 x 125 = “156” + “25”
125 x 125 = 15,625

Try it with a huge number…
995 squared = “99 x 100” + “25”
995 squared = “9900” + “25”
995 squared = 990025

Now challenge your friends to give you any two digit number ending in 5.
If you can do your multiplication tables, you can get the square of 75 … just like that….

Try it… 75 squared is?

From before, we learned 45 squared is 2025.

So how to get 46 squared? Take 45, multiply by 2 and add 1. Or 91.

Therefore 46 squared should equal 2116