I have finished it at long last but it is one of the most difficult quizzes ever !
I have had to ask for help and I do try not to !
I am still not sure about some of them and for 27 I can only think of Ruby .
27 +13 = 40 Ruby for fortieth WA.
The other answer I thought it might be is element numbers
27 = CO cobalt
13 = AL Aluminum
CO + AL = Coal
I am tossing a coin here !