1. UPC, Bar codes, Zip + 4 (Post Net) Sol: DM.11
Classwork:
Power point examples
Homework (day 48):
Quiz next block
Practice questions from blog (1-12)

2. Bar Codes: https://www. youtube. com/watch
Bar Codes: How Bar Codes Work:
The simplest bar code is the post net code for the zip + 4 with a tenth digit for error correction. The code is made up of 52 vertical bars with two possible lengths (long and short). The beginning and the end bars are called the guard bars. Blocks of five represent three short bars. The check digit is chosen so that the sum of the ten digits is evenly divisible by ten.

5. Zip + 4 and Post Net Code https://www.youtube.com/watch?v=KZWgioyrmBU
This code has ten digits
The sum of the digits in the zip + 4 and the check digit must be evenly divisible by ten.
Ex: What is the post net code if the zip code is:
= 45
The check digit would have to be a five to make the number divisible by ten.
The post net code would be:

6. Universal Product Code (UPC) https://www. youtube. com/watch
Universal Product Code (UPC) the scheme used on grocery products. The first digit identifies a broad category of goods, the next five digits identifies the manufacturer, the next five identifies the product and the last is a check.
Find the sum of the digits in positions: 1, 3, 5, 7, 9 and 11
Triple the result
Add the remaining digits
Find the total of both results
The check digit should make the total end in zero.

7. Ex: Determine the check digit that should be appended to the UPC identification number:
= (3) = = = 60 Therefore 60 is the check digit because it ends in zero.