Practice 3: Zipcodes

Prepared by:

Joseph Malkevitch
Department of Mathematics and Computer Studies
York College (CUNY)
Jamaica, New York 11451


web page:

1. Decode the binary string that appears on an envelop that arrives at your home address and verify that it is the zipcode you use. What is the check digit for your home zipcode?

2. York's zipcode is 11451-0001. Find the check digit for this zipcode and code in binary (with the guard bars) the zipcode and its check digit.

3. Determine the check digit for the CUNY Graduate Center:


and translate the digits including the check digit into the appropriate binary string with guard bars.


You might enjoy this general article about zipcodes.