Look there is a Caesar salad on the (periodic) table!
If
2 + 4 = 3
7 + 1 = 8
12 + 1 = 113
13 + 2 = 112
20 + 1 = 105
Then what does 10 – 1 equal?
Still stuck on the most cryptic of our GCHQ Puzzle Challenges so far? Making you depressed? Consider this a hint! Good luck!