Determine the check digit (as described in the text) that should be appended to the blood bank identification number 312545006987005.
A) 4
B) 3
C) 7
D) 6

Question

Quizplus · Accepted Answer

To calculate the check digit, we need to follow these steps:
1. Starting from the leftmost digit, multiply each alternate digit by 2. The digits on even positions are: 1, 5, 5, 0, 7, and 5.
2. Add up the individual digits of the products obtained in step 1. For example, 5 x 2 = 10, so we add 1 + 0 = 1.
3. Add up the digits in the odd positions: 3 + 2 + 4 + 0 + 9 + 8 = 26.
4. Add the results from step 2 and step 3: 1 + 1 + 5 + 0 + 7 + 5 + 2 + 6 = 27.
5. The check digit is the number that needs to be added to the result obtained in step 4 to make it a multiple of 10. In this case, the nearest multiple of 10 greater than 27 is 30. Therefore, the check digit is 30 - 27 = 3.

So the correct answer is A) 4.

Determine the Check Digit (As Described in the Text) That