At first, I thought this question ridiculous and certainly posted by a troll. But, then I thought about it, and can see why it might be confusing.
For example, it's difficult and perhaps meaningless to do an average if measuring for average temperature.. If you wanted to do an average, then you would need, for example, 24 equally divided parts of the globe.
The places would have to be an apples-to-apples comparison to the other 23 parts. You would have to measure those EXACT same places for DECADES, without any interference from heat inducing urbanization.
Instead, we have a hodge-podge of different geographies and movement that make the comparison apples to bowling balls. Some places urbanize, which makes the temperature warmer. Many weather stations close permanently, so consistency is greatly compromised. Temperature measuring instruments change over time from analog to digital, further compromising continuity. Climate models can be horribly inaccurate.
We depend on climate models too much for averages. Atmospheric Scientist Dr. Joanne Simpson said of climate models: "The main basis of the claim that man’s release of greenhouse gases is the cause of the warming is based almost entirely upon climate models. We all know the frailty of models concerning the air-surface system."
Nations of equal size have different numbers of weather stations. How can you possibly do an average if rich Country A is using 100 thermometers, but poor Country B is using ten thermometers? An analogy would be I measure the temps of all my 100 cooked turkeys, but the other person only measures the temperature of every 10th turkey he cooks. Do you think you are comparing the same thing?
Another example. LeBron James' team scores 100 points. Lebron scores 60 points, while 9 other players score the other 40. If someone said the average of each player was 10 points (100/10 = 10), then you can see the problems you get into.
BTW, There is a fake Dirac running around here. But you can always tell fake Dirac from real Dirac because I leave my profile open.