30 math tricks for fast calculations

  • 578 Views
Uploaded By: Adam Rangihana . Category: General . Added on: 14 April 2016.
In this Video:
Description
Please thumb up if you like the video.

Please feel free to ask any question. We will try to answer as soon as we can.

https://www.facebook.com/GargUniversi...

Check out the Trick Questions from Garg University

https://www.facebook.com/notes/garg-u...

You can also subscribe to our channel at following link.

http://www.youtube.com/subscription_c...




After applying an arithmetic operation to two operands and getting a result, you can use this procedure to improve your confidence that the result is correct.
Sum the digits of the first operand; any 9s (or sets of digits that add to 9) can be counted as 0.
If the resulting sum has two or more digits, sum those digits as in step one; repeat this step until the resulting sum has only one digit.
Repeat steps one and two with the second operand. You now have two one-digit numbers, one condensed from the first operand and the other condensed from the second operand. (These one-digit numbers are also the remainders you would end up with if you divided the original operands by 9; mathematically speaking, they're the original operands modulo 9.)
Apply the originally specified operation to the two condensed operands, and then apply the summing-of-digits procedure to the result of the operation.
Sum the digits of the result you originally obtained for the original calculation..
If the result of step 4 does not equal the result of step 5, then the original answer is wrong. If the two results match, then the original answer may be right, though it isn't guaranteed to be.
More