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Squaring a two or three digit number ending in 5.

    If you need to square a number (two or three digits) that ends in 5, just use this trick.  First, you should know that when any number squared that ends in 5 will always have the last two digits of 25.  Then all ya need to do is look at the digits before the 5 and multiply it (them) by the next number higher and put that infront of the 25.

Here's two examples: 

1) 35 squared is 3 times 4 (one higher than 3) or 12 and put that in front of 25. Looks like this... 1225

2) 65 squared is 6 times 7 (one higher than 6) or 42 and put that in front of 25.  Looks like this .... 4225