APPLICATIONS OF DIGIT SUM METHOD
The digit-sum method has immense utility for practitioners of Numerology and other occult sciences. The knowledge that they can eliminate the 9’s and numbers that add up to 9 makes their task simpler.
For students giving competitive and other exams. this technique has a lot of utility. Many times they can check the digit-sum of each of the alternatives with the digit-sum of the question and try to arrive at the correct answer. This will eliminate the need for going through the whole calculation.
However, there is one drawback with this technique. The drawback is that the digit-sum method can tell us only whether an answer is wrong or not. It cannot tell us with complete accuracy whether an answer is correct or not.
This sentence is so important that I would like to repeat it again.
The digit-sum method can only tell us whether an answer is wrong or not. It cannot tell us with complete accuracy whether an answer is correct or not.
Let me illustrate this with an example.
(Q) What is the product of 9993 multiplied by 9997?
Method: Assume that you have read the question and calculated the answer as 99900021. The digit sum of the question is 3 and the digit sum of the answer is 3 hence we can assume that the answer is correct.
However, instead of 99900021 had your answer been 99900012 then too the digit-sum would have matched even though the answer is not correct. Or for that matter if your answer would have been 99990021 then too the digit-sum would have matched although this answer is incorrect too. Or in an extreme case, even if your answer would have been 888111021 then still the digit-sum would have matched although it has highly deviated from the correct answer!
Thus, even though the digit-sum of the answer matches that of the question, you cannot be 100% sure of its accuracy. You can be reasonably sure of its accuracy but cannot swear by it.
However, if the digit-sum of the answer does not match the digit sum of the question then you can be 100% sure that the answer is wrong.
In a nutshell,
- Then the answer is matched Then Most likely correct.
- If the digit-sums Do not match then Wrong.
For practitioners of numerology and other occult sciences, there is no question of checking answers and hence this can per se come to their aid.
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