1. How is bold or italics shown for (a) a standalone fraction, (b) one in a series of fractions, (c) a mixed number where (i) just the whole number portion is in italics, (ii) where just the fractional portion is in italics, (iii) where the entire whole number is in italics? 2. How is bold or italics shown in a compound expression where a fraction in joined to a word, as in "1/2-off"? (a) if the 1/2 is in a non-regular typeform, (b) where both parts are in the same non-regular typeform, (c) where both parts are in different non-regular typeforms? 3. How is bold AND italics shown for the situations described above with fractions and mixed numbers?
I discussed this situation with the BANA Math Committee and the consensus is that the Code does not address typeform for fractions. Since there is nothing in the Code, the transcriber will have to devise some way to show the typeface if it is necessary. A tn was the most agreed upon solution. The indicator system that is used for whole numbers is not applicable to mixed numbers, although a fraction by itself could be enclosed in begin and end typeform indicators.
This is something that will have to be discussed at an official level and perhaps a solution can be arrived at.
Of course if the typeform is not mathematical or significant, Section 34b says it must not be shown in the transcription.