Given the same problem:

• Speed of motorboat in still water = $15$ km/h
• Downstream distance = Upstream distance = 30 km
• Total time = 4 hours 30 minutes = $4.5$ hours

Let the speed of the stream be $x$ km/h.

Equations for downstream and upstream:

• Downstream speed = $15 + x$ km/h
• Upstream speed = $15 - x$ km/h

The time taken for downstream and upstream travel is: $\frac{30}{15 + x} + \frac{30}{15 - x} = 4.5$

I'll solve this equation again to determine the speed of the stream, as you asked for it directly.# Re-solving the equation based on the same problem setup speed_of_stream = solve(total_time_eq, x) speed_of_streamThe speed of the stream is $5$ km/h.

Would you like more clarification on the process, or any additional details?

Here are five related questions:

1. How would the time change if the stream speed were reduced to 3 km/h?
2. What happens if the boat's speed in still water increases to 20 km/h?
3. How can you calculate the time for just one leg of the journey (downstream or upstream)?
4. What other factors could affect a boat’s speed in a real-life scenario on a river?
5. How would the problem be different if the boat traveled on a circular path rather than a straight river?

Tip: Always verify that the solution satisfies the physical conditions of the problem, such as keeping speed positive.