Excluding stoppages, the speed of a bus is 70 kmph andincluding stoppages, it is 56 kmph. For how many minutes does the busstop per hour?

Options

A. 10 min
B. 8 min
C. 15 min
D. 12 min

Answer

To solve the problem, we need to determine how many minutes the bus stops per hour based on the given speeds.

### Step-by-Step Solution:

1. **Identify the Speeds**:
- Speed excluding stoppages = 70 km/h
- Speed including stoppages = 56 km/h

2. **Calculate the Loss of Speed**:
- Loss of speed due to stoppages = Speed excluding stoppages - Speed including stoppages
- Loss of speed = 70 km/h - 56 km/h = 14 km/h

3. **Determine the Time Taken to Cover the Lost Distance**:
- The loss of speed (14 km/h) indicates how much distance the bus would have covered if it had not stopped.
- To find out how long the bus stops, we need to find the time it takes to cover this lost distance at the speed excluding stoppages.

4. **Use the Formula for Time**:
- Time = Distance / Speed
- Here, the distance covered during stoppages can be considered as the distance that would have been covered in the time stopped.
- Distance = 14 km (the distance lost due to stoppages)
- Speed = 70 km/h (the speed of the bus when it is moving)

5. **Calculate the Time**:
- Time = 14 km / 70 km/h = 1/5 hours

6. **Convert Time to Minutes**:
- Since 1 hour = 60 minutes, we convert 1/5 hours to minutes:
- Time in minutes = (1/5) * 60 = 12 minutes

### Final Answer:
The bus stops for **12 minutes per hour**.

---