A clock is set right at 5 AM. The clock loses 16 minutes in 24 hours. What will be the true time when the clock indicates 10 p.m. on 4th day?
First, we find the total hours shown by the incorrect clock from the start time to the end time.
The duration is:
The clock loses 16 minutes in 24 hours. This means for every 24 hours of correct time, the faulty clock only shows 23 hours and 44 minutes.
So, $\frac{356}{15}$ hours on the faulty clock is equivalent to 24 hours of correct time.
We can set up a proportion to find the correct duration ('x') corresponding to the 89 hours shown on the faulty clock.
If $\frac{356}{15}$ faulty hours = 24 correct hours
Then, 89 faulty hours = $89 \times \frac{24}{\frac{356}{15}}$ correct hours.
Since $356 = 4 \times 89$, we can simplify:
$x = \frac{89 \times 24 \times 15}{4 \times 89} = \frac{24 \times 15}{4} = 6 \times 15 = 90$ hours.
So, the actual time that has passed is 90 hours.
We add the 90 hours of correct time to the initial start time.
Adding 3 full days to 5 a.m. (Day 1) brings us to 5 a.m. on Day 4.
Now, add the remaining 18 hours to 5 a.m. on Day 4:
5 a.m. + 18 hours = 23:00, which is 11 p.m.
The correct time is 11:00 PM on the fourth day.
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