This could be a silly question, but I'm a bit confused with this concept.
Don't we say usually the purchasing power(or value) of currency(or money) is low when the price level is high in one country(i.e. negative relationship)?
However, in international economics, it looks like a country's price level has postive relation to purchasing power of it's own currency.
For example, the prices of United States are higher than that of Korea and at the same time, the purchasing power of dollar is higher than Korean won.
How can I understand this kind of contradiction?