That question is equivalent to asking a human to add the wavelengths of those two colors and divide it by 3.
Unfair - human beats AI in this comparison, as human will instantly answer "I don't know" instead of yelling a random number.
Or at best "I don't know, but maybe I can find out" and proceed to finding out/ But he is unlikely to shout "6" because he heard this number once when someone talked about light.
Unless you're aware of hyperspectral image adapters for LLMs they aren't capable of that either.