Consider exactly at 9 : 00, minute hand is at position '12' and hour hand is at '9' hence angle between these two hands at 9 : 00 is 270°
Since relative speed between them is 11/2° per minute or every minute the minute hand will travel 11/2° more than the hour hand.
Then will be together when the minute hand will travel (270 - 180) = 90° more than the hour hand. And time taken for this is (90)/(11/2) = 180/11 or 16 4/11 minute
Hence they will be opposite to each other at 9 : 49 minute : 21.81 second
