Chapter 2 - Set Theory - 2.1 Basic Set Concepts - Exercise Set 2.1 - Page 59: 112

{New Zealand}

{x|x is a country in which the percentage having used marijuana $\geq$ 22.2%} In the graph there is one country in which the percentage having used marijuana $\geq$ 22.2% is New Zealand New Zealand = 22.2% therefore the answer = {New Zealand}