How to read barcode

Choosing to store a particular product, we in vain do not pay attention to his bar-code. It is applied on almost any package and consists of a set of lines and written under these numbers. Knowing simple rules, you can see a fake in front of you or not.

Instruction

1. Look at the barcode. According to the European standard, it must contain 13 digits. The first two identify the country, the next five - code of the enterprise, then the five digits of the encrypted consumer properties (the name of the product, consumer characteristics, weight, composition, color).
2. Calculate the last digit of the barcodeand control, which is designed to determine the authentication code. For this you need to add up the numbers that stand on even ground. This amount and multiply by three. Then add the numbers that are located at odd places, except the last. Fold the two results. Drop from the sum of the first digit. Of the ten, subtract the last result. You should get a number that is equal to the last control. Therefore, before you original product. If it did not happen, most likely the goods are fake.For example, take the barcode "4823061430014":1. The addition of numbers that are located in even places: 8+3+6+4+0+1=22;
   2. Multiply result by 3: 22х3=66;
   3. The addition of numbers that are located at odd places, except the last one: 4+2+0+1+3+0=10;
   4. Addition sums of numbers: 66+10=76;
   5. Remove the first digit: 76-70=6;
   6. Subtract the resulting number from 10: 10-6=4.The checksum is 4, which corresponds to the last digit of the barcode.