The distance between place X and Y is 720 km. An express train leaves place X at 5:00 p.m. and runs at a speed of 45 km/hr. The train stops on the way for 45 minutes. At what time (in a.m.) the train reaches at place Y?

Options

A. 1:45
B. 9:45
C. 7:15
D. 12:15

Answer

To solve the problem, we need to determine the total time taken by the train to travel from place X to place Y, including the time spent on the journey and the stop time.

### Step 1: Calculate the time taken to travel 720 km at a speed of 45 km/hr.
To find the time taken (in hours) to cover a distance, we can use the formula:
\[ \text{Time} = \frac{\text{Distance}}{\text{Speed}} \]
Here, the distance is 720 km and the speed is 45 km/hr.

\[ \text{Time} = \frac{720 \text{ km}}{45 \text{ km/hr}} = 16 \text{ hours} \]

### Step 2: Convert the stop time from minutes to hours.
The train stops for 45 minutes. To convert this into hours, we divide by 60 (since there are 60 minutes in an hour):
\[ \text{Stop Time} = \frac{45 \text{ minutes}}{60} = 0.75 \text{ hours} \]

### Step 3: Calculate the total travel time.
Now, we add the travel time and the stop time together:
\[ \text{Total Time} = \text{Travel Time} + \text{Stop Time} = 16 \text{ hours} + 0.75 \text{ hours} = 16.75 \text{ hours} \]

### Step 4: Determine the arrival time.
The train leaves at 5:00 p.m. To find the arrival time, we need to add 16.75 hours to 5:00 p.m.

First, we convert 16.75 hours into hours and minutes:
- 16 hours and 0.75 hours = 16 hours and 45 minutes.

Now, we add this to 5:00 p.m.:
- 5:00 p.m. + 16 hours = 9:00 a.m. (next day)
- 9:00 a.m. + 45 minutes = 9:45 a.m.

Thus, the train reaches place Y at **9:45 a.m.**

### Final Answer:
The train reaches place Y at **9:45 a.m.**

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