Blimey, it's hard to find figures without running across Holocaust denial stuff
Anyway, I finally found a table which may or may not be accurate here - world Jewish population in 1948 was:
Europe 3.7m
Asia 1.3m
Africa, Middle East 0.7m
N & S America 5.8 m
Australia -
Total 11.5m
(1938 total 16.6m....)