Have the class use a multiplication shift in their cipher by multiplying a constant to each letter's numeric value. For an example, let's have a constant of 5. In this case, C=2. Multiply 5 by that, to get 10. Convert that back to a letter, 10=K.
Remember when we added constants in the previous section? You go through the same process, but with multiplication: Let's take G=6. Multiply by our constant of 5 and we get 30.
You can just keep going around the alphabet wheel. So G would end up being E.
With a constant of 5, the message "I really like code messages" is encoded to be the following:
O HUADDQ DOYU KSPU IUMMAEUM.
For the Caesar Cipher, we will be using a combination of the multiplication shift and the addition shift.
This can be done using the equation of a linear function: y=mx + b
The m value is the multiplication shift and the b value is the addition shift.
Encourage discussion on how to tackle the deciphering: