Depending on whose formula is used, to replace 50gm fresh yeast, one should use anywhere from 8 to 32.5 gm active dry yeast. My sister put together this following handy conversion chart:
Here's why this all came about: While I was searching for compressed yeast at the supermarket, I looked at the shelves to see Fleischmann's "active dry", "instant - bread machines", "instant - quick rise", and [get ready for this...] "instant - pizza crust yeast". What?!! As usual, I chose "active dry". (If I lived in the USA, "fresh compressed" would be an option. But for some unknown reason, Fleischmann's fresh yeast is not available in Canada.)
And why do I always choose Fleischmann's active dry yeast over the other kinds of dried yeast? Because that's what my mother always uses.