Monday, January 28, 2013

Math Fun Facts


Squares of a Number Ending in 5

There's a quick way to do this: if the first digit is N and the second digit is 5, then the last 2 digits of the answer will be 25, and the preceding digits will be N*(N+1)

For instance 
2052 = 42025, since (20*21)25 = (420)25-- 42025
452 = 2025,    since (4*5)25= (20)25 -- 2025
852 = 7225,    since (8*9)25= (72)25-- 7225

Hope this helps...

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