Chapter 8.5, Problem 64E

To determine

The cryptogram decoding using encoded matrix.

Answer to Problem 64E

The message is

  

Explanation of Solution

Given information:

  

Formula used:

Matrix multiplication is used.

Calculation:

We have to decode the following cryptogram:

5 2 25 11 -2 -7 -15 -15 32 14 -8 -13 38 19 -19 -19 37 16

Using the some unknown decoding matrix

Dividing them into matrices we get,

  

The last word of the message is _SUE.

So,

  

The first two letters of the last word are _ &. S. So,

  

Also we have

  

The last two letters of the last word are U &. E. So,

Using we get,

  

Thus,

  

And we get

  

Thus,

Thus, we have

  

Now to get the uncoded row matrices,

Coded matrix Decoding matrix Uncoded Matrix

  

  

We get the following uncoded row matrices,

  

Splitting them we get,

3 1 14 3 5 12 0 15 18 4 5 18 19 0 0 19 21 5

When the numbers are converted to the alphabets they are assigned to we get the message

  

Conclusion:

When the numbers are converted to the alphabets they are assigned to we get the message