Step-by-step Solution:

Quick Solution

This is a time calculation puzzle. We can solve it by working backward from the known future event (the next visit) to find the time of the previous visit, and then use that to find when the statement was made.

1. Calculate the Time of the Previous Visit

• We know the doctor's next visit is scheduled for 1:40 PM.
• We also know the interval between visits is 3 hours and 30 minutes.
• To find the time of the previous visit, we subtract the interval from the time of the next visit:

1:40 PM - 3 hours 30 minutes = 10:10 AM

So, the doctor's last visit was at 10:10 AM.

2. Calculate the Time the Statement was Made

• The doctor says, "I have already gone to the patient 1 hour 20 minutes ago."
• This means the time he is speaking is 1 hour and 20 minutes after his last visit.
• We can now calculate the exact time the information was given:

10:10 AM + 1 hour 20 minutes = 11:30 AM

Final Answer: The information was given to the compounder at 11:30 A. M.