Hello,
I'm just testing the 1.7.2-3 version under cygwin.
Here is what I've found.

guile> 11/3
11/3
guile> (inexact->exact 11/3)
11/3

At the same place the 1.6.7 version responces like that:

guile> 11/3
3.66666666666667
guile> (inexact->exact 11/3)
4

Roman