What is the first time after 3PM when the hour and minute hands of a clock are exactly on top of each other?
Answer
At 3hr 16 min 21.82 (somewhere between 21 and 22 seconds) seconds.
By the time the minute hand gets to 3, the hour hand would have moved a little, so they will not be exactly on top of each other at 3.15PM.
The minute hand and hour hand move 360 degrees and 30 degrees respectively in 60 minutes.