Given the reference text about the history of the Olympic marathon distance, tell me what was the distance of the Olympic marathon during the 1924 Olympics in Paris in kilometers?

The International Olympic Committee agreed in 1907 that the distance for the 1908 London Olympic marathon would be about 25 miles or 40 kilometers. The organizers decided on a course of 26 miles from the start at Windsor Castle to the royal entrance to the White City Stadium, followed by a lap (586 yards 2 feet; 536 m) of the track, finishing in front of the Royal Box. The course was later altered to use a different entrance to the stadium, followed by a partial lap of 385 yards to the same finish.

The modern 42.195 km (26.219 mi) standard distance for the marathon was set by the International Amateur Athletic Federation (IAAF) in May 1921 directly from the length used at the 1908 Summer Olympics in London.

The distance of the Olympic marathon in 1924 would have been 42.195 kilometers, since this is the standard distance set by the IAAF in 1921.