To answer this question, we will Assign each letter a value relative to its position in the alphabet, let us show this through a picture
Now we have to discover with this encoding, how we can satisfy the following relations:
where the symbols
represent some arithmetic operation that we must discover.
Note that if we sum, the numbers we get
that is, to decoding this operation, we have to add the numbers and then multiply the result by 2. So the result of the code BITMAP is