The calculated distance (air line) between Petaling Jaya and Kuala Selangor is approximately 30 miles respectively 48 kilometers.
By car or train, the actual journey to Kuala Selangor is certainly longer, as only the direct route (as the crow flies) between Petaling Jaya and Kuala Selangor has been calculated here.
Air line (approximately)
48 kilometers
26 nautical miles