Convert from quadrant to stadium

Unit Definition (quadrant)
The quadrant is a unit of distance equal to the distance from the North Pole to the Equator. The metric system was originally designed to make this distance exactly 10 million meters (6213.71 miles). The actual meter comes close to the design. Using the conventional figures of 12 756 kilometers for the equatorial diameter of the earth and 12 714 kilometers for the polar diameter, and assuming the earth to have elliptic cross section, the length of the quadrant is about 10 001 300 meters (6214.52 miles). In principle, the quadrant is divided into 5400 nautical miles; in fact, 5400 international nautical miles equal 10 000 800 meters.

Unit Definition (stadium)
The stadium is a historic unit of distance originating in ancient Greece. Greek athletic fields were all of roughly the same size, and the stadion, equal to 600 podes (feet), was the traditional length of the field. Archaeological measurements show that the stadion was a little more than 200 yards or a little less than 200 meters. The stadion at Olympia, where the original Olympic Games were held, measures 630.8 feet or 192.3 meters; at Athens the stadion was 606.9 feet or 185.0 meters. Stadium is the Latin spelling; in the Roman world the stadium was equal to 625 Roman feet (pes) or 1/8 Roman mile. This is equivalent to 606.95 feet, 202.32 yards, or 185.00 meters. The plural is stadia.