Let's break down the information given:
The clock turns 16 minutes less in 24 hours: This means that the clock is running slow by 16 minutes every day.
The clock is started at 5 o'clock in the morning and shows ten o'clock at night on the fourth day: From 5 o'clock in the morning to 10 o'clock at night, there are 17 hours. Since this happens on the fourth day, it means that the clock has been running for 3 full days before reaching ten o'clock at night.
Now, let's calculate the total time discrepancy introduced by the clock's slowness over these 3 full days:
Total discrepancy = (16 minutes/day) × (3 days) = 48 minutes
Since the clock is running 16 minutes behind every day, over 3 days, it accumulates a total delay of 48 minutes.
To find the correct time, we need to subtract this discrepancy from the time shown on the clock, which is ten o'clock at night:
Correct time = 10:00 PM - 48 minutes
To subtract the minutes, we can convert 48 minutes into hours by dividing it by 60:
48 minutes ÷ 60 = 0.8 hours
Now, subtracting 0.8 hours from 10:00 PM:
Correct time = 10:00 PM - 0.8 hours = 9:12 PM
Therefore, the correct time is 9:12 PM.