UPC Codes Credit Cards What is it A

UPC Codes Credit Cards

What is it? • A UPC is a 12 digit code generally used to identify a product. • Can also be used as coupons • Why use a UPC instead of just a price tag? • Can change price in computer easily • Universal PRODUCT Code not Universal PRICE code • If you decided to change the price of an item you would have to but new bar codes on everything!

Parts of the code

How is a code valid? The purpose of a check digit is to guard against input errors or fraud. Follow these steps: 1. Underline the odd positions, add them up. 2. Multiply by 3 3. Add the even positions up 4. Add the two together 5. The sum must end in a 0 to be valid

1. ) Show that 0 -1 2 3 4 5 -6 7 8 9 0 -5 is a valid UPC number. Add the odd positions 0 + 2 + 4 + 6 + 8 + 0 = 20 Multiply by 3 20 x 3 = 60 Add the even positions (don’t add the check digit) 1 + 3 + 5 + 7 + 9 = 25 Add the two together 60 + 25 = 85 Add a 5 so the sum ends in zero 85 + 5 = 90 Since the number added is the same as the check digit, then the code is VALID!

1. ) Determine if 6 – 7 1 8 6 0 – 0 1 3 6 6 – 4 is a valid UPC number. If not, change the check digit to make it valid! Add the odd positions 6 + 1 + 6 + 0 + 3 + 6 = 22 Multiply by 3 22 x 3 = 66 Add the even positions (don’t add the check digit) 7 + 8 + 0 + 1 + 6 = 22 Add the two together 66 + 22 = 88 Add a 2 so the sum ends in zero 88 + 2 = 90 The check digit needs to be changed to 2 in order to make it valid.

1. ) Determine the check digit (d) for the UPC number 23567128942 d. Add the odd positions 2 + 5 + 7 + 2 + 9 + 2 = 27 Multiply by 3 27 x 3 = 81 Add the even positions (don’t add the check digit) 3 + 6 + 1 + 8 + 4 = 22 Add the two together 81 + 22 = 103 Add a 7 so the sum ends in zero 103 + 7 = 110 d=7

Credit Cards

How is a credit card valid? Follow these steps: 1. Add the odd position digits 2. Multiply by 2 3. Add the number of odd position digits greater than 4 4. Add the even position digits 5. The sum must end in a 0 to be valid

1. ) Show that 4024 0706 1620 3102 is a valid credit card number. Add the odd positions 4 + 2 + 0 + 1 + 2 + 3 + 0 = 12 Multiply by 2 12 x 2 = 24 Add the number of odd position digits greater than 4 (None) 24 + 0 = 24 Add the even positions (don’t add the check digit) 0 + 4 + 7 + 6 + 0 + 1= 24; 24 + 24 = 48 Add a 2 so the sum ends in zero 48 + 2 = 50 Since the number added is the same as the check digit, then the code is VALID!

1. ) Determine if 5529 4203 5061 5465 is a valid credit card number. If not, change the check digit to make it valid. Add the odd positions 5 + 2 + 4 + 0 + 5 + 6 = 33 Multiply by 2 33 x 2 = 66 Add the number of odd position digits greater than 4 (5, 5, 6) 66 + 5 = 71 Add the even positions (don’t add the check digit) 5 + 9 + 2 + 3 + 0 + 1 + 4= 24; 71 + 24 = 95 Add a 6 so the sum ends in zero 95 + 5 = 100 Since the number added is the check digit, it is VALID!

1. ) Determine the check digit (d) for the credit card number 4232 0067 3456 567 d. Add the odd positions 4 + 3 + 0 + 6 + 3 + 5 + 7 = 33 Multiply by 2 33 x 2 = 66 Add the number of odd position digits greater than 4 (6, 5, 5, 7) 66 + 4 = 70 Add the even positions (don’t add the check digit) 2 + 0 + 7 + 4 + 6 = 27; 70 + 27 = 97 Add a 6 so the sum ends in zero 97 + 3 = 100; d = 3

ARE YOU READY? ? 0 -51231 -69421 -5 1. ) Is the following UPC numbers valid codes 2. ) Find the check digit (d) for the UPC numbers 0 -32692 -03012 d 3. ) Is the following Credit Card number valid? 4716 5868 1970 205 6 4. ) Find the check digit (d) for the Credit Card number 5310 6275 7512 805 d