A clock is set right at 5 a.m. The clock loses 16 minutes in 24 hours. What will be the true time when the clock indicates 10 p.m. on 4th day?

A. 8 p.m
B. 9 p.m
C. 10 p.m
D. 11 p.m
Ans: D

Explanation:

Time from 5 a.m. on a day to 10 p.m. on 4th day = 89 hours.
Now 23 hrs 44 min. of this clock = 24 hours of correct clock.
=> 356/15 hrs of this clock = 24 hours of correct clock.
= 90 hrs of correct clock.
So, the correct time is 11 p.m.