How to implement review ratings with Fivestar?
Yes, you can do it, you can combine the Views module with the Views Aggregator Plus or with the Views Calc module.

Views Calc:


  Adds simple calculations to a views table. You can SUM, AVERAGE, COUNT, MIN, MAX, or AVG selected columns. A plug
  in theme makes the view look more spreadsheet-like (right justifies
  numeric fields, shades calculated columns and rows, and underlines
  calculated rows).


Views Aggregator Plus:


  In addition to what Views and Views Calc do, this module:
  
  
  enumerates group members
  produces tallies, i.e. textual histograms
  aggregates on Views PHP code-snippet evalutations
  can filter out result rows on regexp patterns
  gives you sorting on Views' Math expressions
  can process Webform submissions
  lets you add your own custom aggregation functions
  
  
  ... and it puts summary statistics at the bottom of your aggregated
  table as well!