Determine the check digit that should be appended to the bank identification number 05200035.
A) 1
B) 3
C) 8
D) 9

Question

Quizplus · Accepted Answer

To determine the check digit, we use the Luhn algorithm, where we multiply every other digit by 2, and add the digits of the resulting products together. Then, we add the sum of the digits that were not multiplied by 2. Finally, we subtract this total from the nearest equal or higher multiple of 10. 
In this case, the calculation would be: 
0+5+2*2+0+0+0+3*2+5 
= 0+5+4+0+0+0+6+5 
= 20 
The nearest multiple of 10 is 30. 
Thus, the check digit should be (30-20) = 10-20 = 9. Therefore, the answer is D.

Determine the Check Digit That Should Be Appended to the Bank