| True area | On the old Mercator map | Distortion vs truth |
| Guinea-Bissau | 32,044 km² | 33,646 km² | 1.1× |
| Greenland | 2,154,754 km² | 25,447,645 km² | 11.8× |
| Africa | 30,370,000 km² | — | 1× |
Old maps drew Guinea-Bissau at about 33,646 km² km². The truth is 32,044 km² km² — a difference of 5%% that school atlases carried for centuries.