Clock: A clock only with only dots marking 3, 6, 9 and 12 position has been kept upside down in front of a mirror. A person reads the time in the reflection of the clock as 4.50. What is the actual time ?

A clock with only dots marking 3, 6, 9, and 12 positions, when kept upside down in front of a mirror, shows a reflection time of 4:50. To find the actual time, first find the mirror image of 4:50 by subtracting it from 12:00, which gives 7:10. Then, accounting for the clock being upside down (rotated 180 degrees), the actual time corresponds to 2:40.