Of course these exist and that's why we have the process of rationalization.[0]

https://en.wikipedia.org/wiki/Rationalisation_(mathematics)

A rational number (with a terminating decimal representation or a repeating, non-terminating decimal representation) can always be expressed in fractional p/q form.

I don't think the additional "rational" qualifier is needed for fractions.

Looks like all three replies to this share the same misunderstanding of my intent, so I assume my use of “it’s” was unhelpfully vague.

1/pi is not rational and therefore not “a rational fraction”, but think 1/pi is “a fraction”.

Your comment brought me to the realization that the relationship doesn't hold both ways. A rational number can always be written as a fraction but a fraction is not always rational. Never considered this before today :)

A rational number is one that can be written as a fraction (of two integers).

What's a rational fraction? Integer parts as opposed to e.g. 1.5/2.3?

1/i = (1/i) * (i/i) = i/(i*i) = i/(-1) = -i