The calculated distance (air line) between Le Mans and Boulogne-Billancourt is approximately 110 miles respectively 177 kilometers.
By car or train, the actual journey to Boulogne-Billancourt is certainly longer, as only the direct route (as the crow flies) between Le Mans and Boulogne-Billancourt has been calculated here.
Air line (approximately)
177 kilometers
95 nautical miles