Keeper 8: UPC Codes S.A.S. #12 1 – 3 Credit Cards S.A.S. #13 1 - 4

WARM UP A farmer challenges an engineer, a physicist, and a mathematician to fence off the largest amount of area using the least amount of fence. The engineer made his fence in a circle and said it was the most efficient. The physicist made a long line and said that the length was infinite. Then he said that fencing half of the Earth was the best. The mathematician laughed at the others and with his design, beat the others. What did he do? Answer: The mathematician made a small fence around himself and declared himself to be on the outside.

Keeper 8: UPC Codes S.A.S. #12 1 – 3 Credit Cards S.A.S. #13 1 - 4

Lets TRY IT!!! Rule: 3 x (Odd spots) + (Even Spots) =

1.) Show that 0-58200-48826-5 is a valid UPC number. 0 - 5 8 2 0 0 - 4 8 8 2 6 - 5 2.) Show that 0-52200-48826-5 is a invalid UPC number. 0 - 5 2 2 0 0 - 4 8 8 2 6 - 5 Valid = 0 Invalid = 2

3.) Determine the check digit (d) for the UPC number 38137009213d.

50,000,000,000,000 Credit Cards

Rule: 2 x (Odd spots) + # of Odd spots > 4 + (Even Spots) = 2.) VISA: 4162 0012 3456 789 d d = 3

3.) What is the check digit (d) for the MASTER CARD number? 4.) Show that 4128 0012 4389 0110 is an invalid Visa credit card number. d = 3 NOT VALID

ARE YOU READY?? 1.) Is the following UPC numbers valid codes 0-51231-69421-5  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