Activity Description Decode encrypted messages to determine the form for an affine cipher, and practice your reasoning and arithmetic skills. Input your guesses for the multiplier and constant. Caesar Cipher III is one of the Interactivate assessment explorers.

Shodor Interactivate utilizes JavaScript technology, you must enable it to effectively use our site.

If you wish to leave JavaScript disabled, you may attempt to view the activity. Here is some additional information about this activity that may not be accessible without JavaScript.

Caesar Cipher III

Place in mathematics curriculum:

• practice students' long division skills
• demonstrate the applications of modular arithmetic
• practice the students' logical reasoning skills

This activity allows the user to experiment with decoding messages using modular arithmetic. This activity would work well in mixed ability groups of four or five for approximately forty-five to ninety minutes.

Preparations for this activity:

• supply some structure for them to use to make reasonable guesses
• show how to solve two step equations
• be flexible on the time spent on this activity.
• encourage the students that they can do this if they give it a good try even though it is tricky and involved.