Closer than most people guess: Greenland (2,154,754 km² km²) is only about 12%% larger than Saudi Arabia (1,925,871 km² km²).
Greenland sits in North America, Saudi Arabia in Asia. On the old Mercator map the latitude gap distorted how large each felt beside the other; at true size the answer is simply 1.1×.
The old map muddied it further: Mercator inflates Greenland about 11.8× and Saudi Arabia about 1.2×, so on a Mercator-style map this pair appears 11× apart instead of the true 1.1×.
Saudi Arabia fits 1× into Greenland.