Hm. Manga is better in teaching arithmetic than manhua. 100 won per copper, 100 copper per silver, 100 silver per gold, so a gold is 100 x 100 x 100 = 1 million won, about 900 USDs. Currently, it is about 15 g of gold, so a reasonable coin.
In the same time, 900 USD is should be enough for a...