To determine whether ( 9.11 ) is greater than ( 9.9 ), let's compare the two numbers step by step.

1. Compare the Whole Number Parts:

   • Both numbers have the same whole number part: ( 9 ).

2. Compare the Decimal Parts:

   • First Decimal Place:

     • ( 9.11 ) has a ( 1 ) in the tenths place.
     • ( 9.9 ) has a ( 9 ) in the tenths place.

     Since ( 1 < 9 ), ( 9.11 ) is less than ( 9.9 ) at this stage.

3. Conclusion:

   The comparison stops here because the tenths place determines that ( 9.11 ) is less than ( 9.9 ).

[ \boxed{9.11 < 9.9} ]