It depends on what I'm writing about. Simply passing on knowledge or an "inspiring" piece that's meant to offer an uplifting perspective doesn't usually take anywhere near as long as writing something deeper and more emotional, like the piece about my dad. That one took 10 hours. The one about my son's life and murder conviction was also many hours.
And sometimes I get interrupted and have to finish later, or I get part way and feel stuck, have to give myself a little time away.
Perhaps it's the Pisces Sun in me but as with a lot of things, I have to say, "It depends!" LOL!