Sample calculation

I have a population of 2000 companies, from them, I'm sending the survey to 400 of the comapnies (a significant sample from the entire population of 2000), how many answers do I need so it would be significant sample of respondents (from the 400)?


Less is more. Stay pure. Stay poor.
How are you selecting the 400? Why do you say it is a significant sample? Your use of 'significant' is confusing and undefined.