How much farm land are we all worth?

Question:The average north american eats 140 potatoes a year and it takes 50 sq ft to grow 140 potatoes. so if you add up all the different types of food versus garden plot area, what do you think the final farming land area needed per person per year will be?

Answers:
I'm not sure about all the calculations...But I do know that an acre of land is about what one person can manage (without machinery) and will provide a lot of food.

Some people get enough veggies out of very small plots, like only a couple hundred square feet.

It depends very much on climate, soil and what crops you would want to grow/eat.