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February 2, 2022 at 10:22 am #26469
Hi,
I’m really struggling to understand the DD Method – finding out Odd and Even in particular.
I get that you use the first digit to the left of the decimal point in the odd place, but what about the the other digits?
How do you know which are odd and which are even?
Some examples would be helpful.
Thanks
February 3, 2022 at 3:55 am #26476You must alternate between odd and even.
For example let’s take
9876.1234
Odd is marked as O.
Even is marked as E.
9 8 7 6 . 1 2 3 4
E O E O . E O E O
You start alternating from the left of the decimal place which is odd.
Hope this clarifies
December 10, 2023 at 10:01 pm #45301Hi,
Step 3 of the DD tells us to add 11 to a negative result.
At the same time, it reminds us that, in the end, we should get a single-digit number.
I cannot reconcile these two requirements with the number 10.
Please help!
December 11, 2023 at 5:40 am #45309Hi Salvador
For 10 just keep the digit difference as -1 and the technique should still work.
Example for Addition
16 + 10 = 26
Digit difference of 16 = 5
Digit difference of 10 = -1
5 – 1 = 4
Digit difference of 26 = 4
Example for Subtraction
16 – 10 = 6
Digit difference of 16 = 5
Digit difference of 10 = -1
5 – (-1) = 6
Digit difference of 6 = 6
Example for Multiplication
16 x 10 = 160
Digit difference of 16 = 5
Digit difference of 10 = -1
5 x (-1) = -5
Digit difference of 160 = 1 – 6 = -5
Hope this answers your question
December 11, 2023 at 12:10 pm #45313Thank you very much, Abhishek,
For your prompt reply and clarification.
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