To create a Casting Out Elevens digit sum alternately subtract and add each digit starting from the right.
Step 1
Alternately subtract and add each digit starting from the right.
6 - 2 + 5 - 4 + 3 - 2 = 6
If a digit sum yields a number with more than two digits continue calculating the Casting Out Elevens digit sum of the answer until a single digit is reached.
170516 digit sum is 5
6 - 1 + 5 - 0 + 7 - 1 = 16
6 - 1 = 5
If the final Casting Out Elevens digit sum is less than zero then add 11 to it. Remember that in Casting out Elevens adding eleven is essentially the same as adding zero when it comes to the final answer.
158193 digit sum is 2
3 - 9 + 1 - 8 + 5 - 1 = -9
-9 + 11 = 2