4.8.1 Codes

According to Merriam-Webster, a code is “a system of symbols (as letters or numbers) used to represent assigned and often secret meanings.” Codes are used for many things in the modern world, and most are based on a mathematical scheme.

Activity symbol Activity: Codes

Using the Internet or personal knowledge, list some everyday items that use codes.

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Have you used your ATM card recently? Bought a book? Sent a letter through the post?

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There are many ways codes are used. Here are a few, although this is by no means a complete list:

  • Combination locks to protect your property.
  • ZIP/postal codes to identify a particular region of a country.
  • ISBN codes on books and other publications.
  • UPCs/barcodes on food, clothing, and almost any other products you buy.
  • Morse code for communication.
  • Banking codes to protect your money.
  • Credit card security codes.
  • IMEI numbers for mobile devices.

Videoclip symbol Never heard of IMEI numbers? IMEI numbers are intended to protect your cell phone from unintended use. If you’re interested, check out this short video that investigates IMEIs:

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Merriam-Webster Online, s.v. “code,” http://www.merriam-webster.com/ dictionary/ code [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] (accessed September 25, 2012).

4.8 Optional Activities

4.8.2 Having Fun with Math—the Party Puzzle