At the end of step 14: "A list of all the possible combinations Hide/Show: " within this list, under "Possible Yellow Combinations", one of the items is: "Green Triangle + Orange Triangle = 24" This is incorrect. Green is worth 4, orange is worth 2, and triangles are worth 3, so Green Triangle + Orange Triangle = (4*3)+(2*3) = 18 and not = 24. I was given yellow 24 when I did the quest and I can confirm that the combination of green and orange triangles does not work. The other solution given in the guide for yellow 24 is correct and does work.