Assume the world population will continue to grow exponentially with a growth constant $k=0.0132$ (corresponding to a doubling time of about 52 years),
it takes $\frac{1}{2}$ acre of land to supply food for one person, and
there are 13,500,000 square miles of arable land in in the world.

How long will it be before the world reaches the maximum population? Note: There were 6.06 billion people in the year 2000 and 1 square mile is 640 acres.

Answer: The maximum population will be reached some time in the year .
Hint: Convert .5 acres of land per person (for food) to the number of square miles needed per person. Use this and the number of arable square miles to get the maximum number of people which could exist on Earth. Proceed as you have in previous problems involving exponential growth.