Did some quick maths:

~57.3M Sq Mi of total land on Earth = ~36.6B acres

Roughly 40% inhabitable ~14.6B acres

Divided by ~7.9B population ~1.85 acres/person of inhabitable land.

So it seems the creator saw that and left out the of the whole world part.

Did some quick maths:

~57.3M Sq Mi of total lan on Earth = ~36.6B acres

Roughly 40% inhabitable ~18.3B acres

Divided by ~7.9B population ~2.31 acres/person of inhabitable land.

So it seems the creator saw that and left out the of the whole world part.