Nearly a tie: Democratic Republic of the Congo and Greenland differ by barely -8%% in area — about 2,334,703 km² km² against 2,154,754 km² km².
Democratic Republic of the Congo sits in Africa, Greenland in North America. On the old Mercator map the latitude gap distorted how large each felt beside the other; at true size the answer is simply 0.9×.
The old map muddied it further: Mercator inflates Democratic Republic of the Congo about 1× and Greenland about 11.8×, so on a Mercator-style map this pair appears 10.9× apart instead of the true 0.9×.
Democratic Republic of the Congo fits 0× into Greenland.