Answer:
Step-by-step explanation:
The speed boat departed 1.75 hrs after steam boat and sailed for 1.8 hrs.
So total time steam boat sailed = 3.55 hrs
Distance steam boat traveled = 3.55*36.8 = 130.64 km
Distance of speed boat from port = distance of steam boat - distance separating steam and speed boat
= 130.64-86.9
= 43.74 km
Speed of speed boat = 43.74/1.8
= 24.3 km / hr