A clock is set right at 6 am. The clock losses 16 min in 24 h. What will be true time. if the clock indicates 11 pm on 4th day?

Time from 6 am on a day to 11 pm on 4th day = 89 h
Now, 23 h 44 min of this clock = 24 h of correct clock
89 h of this clock = 24 x (15/356) x 89 h of correct clock = 90 h of correct clock
∴ Correct time will be 12 o' clock (mid-night).