10(0/0)

and:

x(y/y) where x=10,y=0

The result of the first, as expected, is indeterminate:

http://www.wolframalpha.com/input/?i=10(0/0)

But the second is 10:

http://www.wolframalpha.com/input/?i=x(y/y)+where+x+%3D+10,+y+%3D+0

Is this a bug?