Answer:
Step-by-step explanation:
If a boat has the speed = 15 miles per hour
Let the speed of the river = v miles per hour
If the boat is moving down stream, that means boat is traveling with the stream of the river.
So the speed of the boat downstream = (15 + v) miles per hour
Since, speed of the river stream is added with the speed of the boat, it will reach the destination earlier than the expectation.
