Afghanistan dwarfs South America: about 642,058 km² km² against 17,840,000 km² km². At true size Afghanistan is about 27.8× larger — the whole of South America fits into Afghanistan roughly 27 times.
The old Mercator map treated both about equally (1.5× vs 1× inflation), so at least their relative sizes were preserved — even if both were drawn at the wrong absolute scale.
Afghanistan fits 27× into South America.