If I want to write the word "n-th" (as in n-th solution, n-th derivative,...), is it more conventional to write `n-ый/n-ая/n-ое` or `n-й/n-я/n-е`, or are both styles equally common? In terms of *pronunciation*, is it always `э́ный/э́ная/э́ное` (e.g., someone who writes n-я wouldn't actually say that as `э́ня`)?

EDIT: I found out later that for every variable `x` it's acceptable to express "*x-th*" as "*xтый*" (e.g., `m-ый = эмтый, n-ый = энтый, j-ый = житый, q-ый = кутый`), and since this works in all cases while the ending *-ный* for *n-ый* doesn't apply to variables ending with a vowel sound, I'll use the *-тый* version.