The calculated distance (air line) between Gan Yavne and Rishon LeTsiyyon is approximately 14 miles respectively 22 kilometers.
By car or train, the actual journey to Rishon LeTsiyyon is certainly longer, as only the direct route (as the crow flies) between Gan Yavne and Rishon LeTsiyyon has been calculated here.
Air line (approximately)
22 kilometers
12 nautical miles