Understanding Bar Code Check Digit Calculation

This video tutorial explains how to calculate the check digit of a barcode, which is the last digit used to verify the accuracy of the barcode's other numbers. The process involves summing certain digits, doubling sums, and subtracting from 10. The video provides multiple examples, including a special case where the final difference is 10, to illustrate the calculation method.

What is the primary purpose of the check digit in a bar code?

• To indicate the country of origin

• To identify the product category

• To provide the price of the product

• To ensure the bar code is scanned correctly

In the first step of calculating the check digit, which digits are summed?

• All digits except the check digit

• Only the even-positioned digits

• Only the odd-positioned digits

• All digits including the check digit

During the second step, what is done after summing the digits in odd positions?

• Add the sum to the check digit

• Subtract the sum from 100

• Double the sum and add to the previous total

• Divide the sum by 2

What is the final step in determining the check digit?

• Add 10 to the final sum

• Divide the final sum by 10

• Subtract the last digit of the sum from 10

• Multiply the final sum by 2

In the example with a check digit of two, what is the sum of the digits in odd positions?

• 34

• 17

• 8

• 68

What is the exception to the check digit calculation when the final difference is 10?

• Use the digit in the tens place

• Use the digit in the hundreds place

• Use the digit in the ones place

• Use the digit in the thousands place

In the example with a check digit of zero, what is the sum of all digits except the check digit?

• 60

• 40

• 80

• 20

What is the sum of the digits in odd positions for the bar code with a check digit of zero?

• 40

• 30

• 10

• 20

How is the check digit verified in a bar code?

• By matching it with the country code

• By checking the product category

• By ensuring it matches the calculated check digit

• By comparing it to the product price

What happens if the final difference in the check digit calculation is not 10?

• The check digit is ignored

• The check digit is the difference itself

• The check digit is recalculated

• The check digit is set to zero