The calculated distance (air line) between Duque de Caxias and Mangaratiba is approximately 48 miles respectively 77 kilometers.
By car or train, the actual journey to Mangaratiba is certainly longer, as only the direct route (as the crow flies) between Duque de Caxias and Mangaratiba has been calculated here.
Air line (approximately)
77 kilometers
42 nautical miles