Mysql join and sum is doubling result

The way to get around this is to create inline views of your aggregates and join on the those results.

SELECT R.title_id, 
       R.revenue, 
       R.cost, 
       F.interest 
FROM   (SELECT title_id, 
               Sum(revenue) revenue, 
               Sum(cost)    cost 
        FROM   revenue 
        GROUP  BY revenue.title_id) r 
       LEFT JOIN (SELECT title_id, 
                         Sum(interest) interest 
                  FROM   fund 
                  GROUP  BY title_id) f 
              ON r.title_id = F.title_id 

Ref: http://stackoverflow.com/questions/11364162/mysql-join-and-sum-is-doubling-result