As displayed in the Microsoft project 2010 screenshot below, why the summary task (Create DS<Batch: file->file>) has 52hrs work whereas the sum of 2 child tasks is just 12h?  

![enter image description here][1]

Solved: **Check to make sure that none of your summary tasks have resources assigned**  


  [1]: https://i.sstatic.net/SqtGF.jpg