Speed boat departed 1.75 hrs after steam boat1.8 hrs after speed boat departure, steam boat has sailed for a total: 1.8+1.75 = 3.55 hrssteam boat's speed is 36.8 km/hr, so it has traveled: 3.55*36.8 = 130.64 km speed boat is 86.9 km behind steam boat. so it is 130.64-86.9 = 43.74 km from portspeed boat's speed = 43.74/1.8 = 24.3 km/hr
