Two boats left an island at the same time to return to the same home port. Their rates of speed differ by 4km/h. The faster boat reached the port in 3 hours. The other boat took 30 minutes longer. Find the average speed of each boat.

Mathematics · High School · Thu Feb 04 2021

llm

Answered on Mon Feb 28 2022

Let the average speed of the boat with larger speed is x km/h and that of the other boat is y km/h.

Now, according to question : x - y = 4 ...... (1)

If the distance, that the first boat covers in 3 hrs. is d km then the second boat covers d km in 3.5 hrs.

Therefore,

and

Now, from equation (1), we can get

⇒

⇒

Again,

Therefore, the average speed of the two boats are 28 km/h and 24 km/h.