Answer:
3 miles per hour
Step-by-step explanation:
Displacement is the overall change in distance or position of an object. It is the shortest distance from the starting point to the ending point. Displacement is a vector quantity.
Velocity is the time rate of change in displacement, it is the ratio of the total displacement to the total time taken. It is given by the formula:
Velocity = displacement / time
The ship sails north for 2 hours, traveling a total of 15 miles. Then the ship turns south and travels 6 miles in an hour.
The total displacement = shortest distance from initial to final point = 15 miles - 6 miles = 9 miles
Total time = (2 hours) + (1 hour) = 3 hours
Velocity = displacement / time = 9 miles / 3 hours = 3 miles per hour