Flight Soekarno–Hatta International Airport departs from Jakarta Soekarno–Hatta International Airport at 09:45 and arrives at Penang Penang International Airport at 13:00.
The flighttime is about 2h 15m. The distance travelled ("as the bird flies"): 765 Km. So the average speed is roughly 340 Km.
There is an 1 hour time difference between Jakarta and Penang