Need simplest function in C#

Hi,
        I need your help in getting the simplest condition to solve this in LINQ or in C#.
I have two fields in a table. start and end. I have inserted a record with 100 as the start and 200 as the end.
The below specified records are invalid, if the user tries to insert.
Start              End
80                  250
90                  150
125                 275
110                 190
 We can achieve this by using so many conditions but I need the simpler way to ...