This probably includes inland fresh water, but excludes non-freshwater internal waters. By which measure Canada is larger, China is larger when it is purely measured on land, but I’m not sure how Canada would feel about having its lakes left out. They are ‘Great’ after all…
I misunderstood the methodology as well (thinking the length of the border was important) and asked myself the same question. But now that I get it Chile is definitely out of the picture. I mean it's not thaaaaat big of a country even though its elongated shape makes you think otherwise.
China is 2 and India is 7, average is 4.5. China is 2 and Pakistan is 33, average is 17.5. India at 7 and Pakistan at 33 average to 20, just off the list.
Russia is rank 1 in the world by land area and China is rank 3. So the average of the two is 2.
Likewise Canada=2 and USA=4; Average=3
Got Angola with 1 second left
https://en.wikipedia.org/wiki/List_of_countries_and_dependencies_by_area#cite_note-3rd-largest-14
But why isn't Chile - Argentina on the list?