How long is a flight from Seoul to Perth?

A random search for departure 31May,Sun shows:

OPTION 1: 14hr 55min
ICN - KUL Malaysia Airlines Flt 067
KUL - PER Malaysia Airlines Flt 127
Flight Duration: 13hr 25min; Layover Time: 1hr 30min; Total Trip Time: 14hr 55min.

OPTION 2: 17hr 55min
ICN - SYD Qantas Airways Flt 368
SYD - PER Qantas Airways Flt 581
Flight Duration: 15hr 15min; Layover Time: 2hr 40min; Total Trip Time: 17hr 55min.