Final answer:
To find the departure time of Ahmad from Lahore, subtract the total travel time from the time of arrival at Murree. By doing the calculations, we find that Ahmed departed Lahore at 12:39 am.
Step-by-step explanation:
The student is asking to calculate the time of departure of Ahmad from Lahore if he spends a total of 6 hours and 49 minutes to reach Murree, starting his journey at 7:28 am.
To solve this, we need to subtract the travel time from the arrival time.
First, convert the travel time into minutes: 6 hours x 60 minutes per hour = 360 minutes, then add the 49 minutes to get a total travel time of 409 minutes.
Next, convert the 7:28 am time to minutes past midnight: 7 hours x 60 minutes per hour = 420 minutes, plus the 28 minutes gives us 448 minutes past midnight.
Now we subtract the travel time from the time Ahmed arrived at Murree: 448 minutes - 409 minutes = 39 minutes past midnight.
Finally, convert the 39 minutes back into hours and minutes: 39 minutes past midnight is 12:39 am.
Therefore, Ahmed departed Lahore at 12:39 am.