Convert from pyong to cuerda

Unit Definition (pyong)
The pyong is a traditional Korean unit of area equal to about 3.306 square meters or 3.954 square yards. The pyong is widely used in Korea to measure areas both inside and outside buildings. The Taiwanese ping corresponds closely to the pyong.

Unit Definition (cuerda)
The Cuerda is a traditional unit of land area in Puerto Rico. The cuerda is equal to about 3930 square meters, 4700 square yards, 0.393 hectare, or 0.971 acre. Because the cuerda and the acre are so close to being equal, they are often treated informally as being equal. Mainlanders sometimes call the unit the "Spanish acre."