This is a Quora question I was asked and here is my answer.
That will depend on additional data.
Do a search for aand you will probably see a lot of options where you can plug in your assumptions to give you the minimum sample size needed.
I post what I see and do in consumer products. But I am just one person with my own perspective. I want your opinion and observations from your point of view. Please comment below so I and others can learn. Thank you!