[AccessD] middle X and Y coordinates

Hello Group,
 
 
I have a table with two fields which are X and Y coordinates. 
 
X                     Y
  97,234           234,632
  98,456           257,678
107,453           278,945
107,234           278,346
109,123           245,567
 
i need as result
 
X                     Y
  97,500           237,500
  97,500           257,500
107,500           277,500
107,500           277,500
 
on the result i would like a distinct.
 


Can this be done in one query?
 
TIA
 
Pedro Janssen