Hello, masterwizard!
#2 could be a dangerous problem . . .
If . , what does equal?
We should not assume that the fraction is already reduced to lowest terms.
If . has been reduced to ,
. . then we have: . . . . for some integer .
Hence: .
Therefore: .
We arrive at the same answer, but if we are required to show our work,
. . janvdl's solution could lose some points.