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say some maths tricks???
1) Multiply Up to 20X20 


    Take 15 x 13 for an example.
    Always place the larger number of the two on top in your mind.
    Then draw the shape of Africa mentally so it covers the 15 and the 3 from the 13 below. 
     Those covered numbers are all you need.
    First add 15 + 3 = 18
    Add a zero behind it (multiply by 10) to get 180.
    Multiply the covered lower 3 x the single digit above it the "5" (3x5= 15)
    Add 180 + 15 = 195. 

2) Age Calculation Tricks:

Step1: Multiply the first number of the age by 5. (If <10, ex 5, consider it as 05. If it is >100, 
       ex: 102, then take 10 as the first digit, 2 as the second one.)
Step2: Add 3 to the result.
Step3: Double the answer.
Step4: Add the second digit of the number with the result.
Step5: Subtract 6 from it. 

3)Maths Tricks with Numbers

Trick 1:Quick Square

Step1: If you need to square a 2 digit number ending in 5, you can do so very easily with this trick.
Step2: Mulitply the first digit by itself + 1, and put 25 on the end.
Step3:That is all!
Step4: Ex:25 ie(2*(2+1))&25
Answer:625

Trick 2: Multiply by 5

Step1: Take any number, then divide it by 2
Step2:If the result is whole, add a 0 at the end.
Step3: If it is not, ignore the remainder and add a 5 at the end.
Step4: 2682 x 5 = (2682 / 2) & 5 or 0
Step5:2682 / 2 = 1341 (whole number so add 0)
Step6:Ans:13410
Step7:Let’s try another:5887 x 5,2943.5 (fractional numbers (ignore remainder, add 5)
Answer: 29435

Trick 3: Tough Multiplication

Step1: If you have a large number to multiply and one of the numbers is even, 
       you can easily subdivide to get to the answer
Step2:Ex:32 x 125, is the same as: 16 x 250 is the same as: 8 x 500 is the same as: 4 x 1000 = 4,000


Trick 4: Subtracting from 1,000

Step1:To subtract a large number from 1,000 you can use this basic rule:
      subtract all but the last number from 9, then subtract the last number from 10:
Step2:Ex:1000-648
Step3: subtract 6 from 9 = 3
Step4: subtract 4 from 9 = 5
step5: subtract 8 from 10 = 2
Answer: 352


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