IdentificationNumbersLessonPlan.pptVIP

Chapter 16: Identification NumbersLesson Plan Identification Numbers Check Digits The ZIP Code Bar Codes Encoding Personal Data * Mathematical Literacy in Today’s World, 7th ed. For All Practical Purposes ? 2006, W.H. Freeman and Company Chapter 16: Identification Numbers Identification Numbers * Identification Numbers Modern identification numbers serve at least two functions: The number should unambiguously identify the person or thing with which it is associated . The number should have a “self-checking” aspect. Code A group of symbols that represent information. Codes have been invented for storing, securing, and transmitting information. Examples: Hieroglyphics, the Greek alphabet, Roman numerals, Morse code, and the “genetic code” used to describe DNA Chapter 16: Identification Numbers Check Digits * Check Digit A digit included in an identification number for the purpose of error detection. Mathematical calculations or schemes are used on the digits of the identification number to assign the check digit. Computers use the check digit to help detect typing errors during data entry to prevent and detect fraud and to find other errors. U.S. Postal Service money order with identification number 6302438384 and check digit 5. The check digit in this case is the calculated remainder after dividing the sum of the first ten digits by 9. Chapter 16: Identification Numbers Check Digits * Example: Consider the number 0 38000 00127 7 found on the bottom of a box of cornflakes. The first digit identifies a broad category of goods. The next five digits identify the manufacturer. The next five digits identify the product. The last is a check digit. Universal Product Code (UPC) A bar code and identification number that are used on most retail items. By using weighted schemes in the calculation of the check digit, the UPC code can achieve greater error detection—up to 100% of all single-digit errors and most other types of errors. Chapter 16