Question

What should be the check digit for the UPC of a tic-tac package whose first 11 digitsare: 0-09800-23798-d?(The check digit is d so determine what that digit should be by using the UPC method.)

Answer 1

The Universal product code (UPC) is an 11-digit set of numbers and the check digit is located to the far right..

To calculate this 12th digit (the check digit), follow the stesp shown;

$\begin{gathered} (1)\text{ Multiply each of the 1st, 3rd, 5th and 7th digits by }3\text{ and then add the results all together} \\ (0\times3)+(9\times3)+(0\times3)+(2\times3) \\ 0+27+0+6 \\ 33 \\ \text{Take the remaining digits (not included above) and }add\text{ them to the total (33)} \\ 0+8+0+3+7+9+8=35 \\ 35+33=68 \\ \text{Next you divide this new total by 10 } \\ \frac{68}{10} \\ 6\text{ rem 8} \\ To\text{ get the check digit, you now subtract the remainder (8) from 10} \\ Check\text{ digit=10-8} \\ \text{Check digit=2} \end{gathered}$

The calculations show that the check digit is 2.