Question

A watch which gains uniformly was observed to be 5 minutes slow at 12 noon on a Sunday. On the subsequent Wednesday at 6:00 p.m., it was noticed that the watch was 5 minutes fast. When did the watch show the correct time?

• A. On Monday at 12 noon
• B. On Monday at 3:00 a.m,
• C. On Tuesday at 3:00 a.m.
• D. On Tuesday at 12 midnight
• E. None of these

Answer 1

Answer: (C)

On Tuesday at 3:00 a.m.

Since the watch is 5 minutes slow at 12 noon on a Sunday and 5 minutes fast on the subsequent Wednesday at 6:00 p.m, it will show the right time at a time exactly mid way of theses 2 times.
hours passed=24+24+24+6=78hrs
mid way will be 39hrs after Sunday noon, which will be 3:00 a.m. tuesdsay.