Query Syntax

Hello,
I have a numeric field in my oralce table contains the following values:

x
-----
12.55
875.69
325.6
2.53
12.56
....
....

I want to write query to get the following values according to x in y numeric field.

y
------
55.12
69.875
6.325
53.2
56.12
.....
.....

It means I want to replace numbers before decimal point by numbers after decimal point and vice versa.

Thanks
-FA