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Sep 11

Math Square Numbers

Posted by: Bruce

Tagged in: Tutorial , Math Magic


Have you seen those square Easter eggs I got one and it was delicious!

This magical maths trick involves square numbers. Remember, you get a square number by multiplying a number by itself. For example 6 x 6 = 36. 36 is a square number.

There is an amazingly quick way of squaring a two digit number which ends in 5. All you have to do is multiply the first digit by the number one more than it, and then put a 25 on the end of your answer.

Eg: 35 squared
3 x 4 = 12
put 25 on the end makes 1225

Note: this only works for two digit numbers that end in 5.
Learn this trick and you will amaze your friends but it helps to know your tables to start with.....otherwise big mistakes can be made!

Comments (2)

Nic Bruce
It's very easy:

35^2 = 3*(3+1) and add 25 on the end of the answer (1225)
75^2 = 7*(7+1) and add 25 on the end of the answer (5625)
and so on...
Bruce , December 06, 2008
I don't get it
I don't get
sophia , December 04, 2008

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