A boat travels 40 km upstream in 5 hours. If the speed of the boat in still wate
Practice Questions
Q1
A boat travels 40 km upstream in 5 hours. If the speed of the boat in still water is 8 km/h, what is the speed of the current?
1 km/h
2 km/h
3 km/h
4 km/h
Questions & Step-by-Step Solutions
A boat travels 40 km upstream in 5 hours. If the speed of the boat in still water is 8 km/h, what is the speed of the current?
Correct Answer: 0 km/h
Step 1: Understand that the boat travels upstream, which means it is going against the current.
Step 2: The boat travels a distance of 40 km in 5 hours.
Step 3: Calculate the speed of the boat while going upstream using the formula: Speed = Distance / Time.
Step 4: Plug in the values: Speed = 40 km / 5 hours = 8 km/h.
Step 5: Let 'x' be the speed of the current. The speed of the boat in still water is given as 8 km/h.
Step 6: When the boat is going upstream, its effective speed is reduced by the speed of the current. So, we can write the equation: Speed of the boat in still water - Speed of the current = Speed upstream.
Step 7: Substitute the known values into the equation: 8 km/h - x = 8 km/h.
Step 8: Solve for 'x': 8 - x = 8, which simplifies to x = 0.
Step 9: Conclude that the speed of the current is 0 km/h.
Relative Speed – Understanding how the speed of a boat is affected by the current when traveling upstream or downstream.
Speed Calculation – Calculating speed using the formula: Speed = Distance / Time.
Algebraic Manipulation – Solving equations to find unknown variables, such as the speed of the current.