Thursday, May 3, 2012

SQUARING A 2-DIGIT NUMBER WHICH ENDS IN 5

TRICKS
STEP 1:Last two digits of the square are always 25.
STEP 2: To find the number which comes before 25, just perform the operation a x (a+1),where a   
                is the digit before 5 in the original number.
STEP 3. By putting the number received in step 2, just before 25 and you get your square.


Example: Find the square of 75?
                  If we want to square 75, we can find the same in the following steps –
STEP 1:1. Last two digits are 25.
STEP 2. The digit before 5 is 7, if we perform a x (a+1) operation on this,then we will be 
                 7 x (7+1) = 56
STEP3. Hence the square of 75, will be 5625.

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