| True area | On the old Mercator map | Distortion vs truth |
|---|
| Western Sahara | 90,820 km² | 108,984 km² | 1.2× |
| Greenland | 2,154,754 km² | 25,447,645 km² | 11.8× |
| Africa | 30,370,000 km² | — | 1× |
Old maps drew Western Sahara at about 108,984 km² km². The truth is 90,820 km² km² — a difference of 20%% that school atlases carried for centuries.