Suppose a researcher is studying a population in which 57% of the population has a certain trait. Round your answer to the nearest tenth of a percent if needed.
The researcher studies a simple random sample of size n = 30. What is the approximate standard deviation of a sampling distribution of the proportion for samples this size? @directrix

Question

Suppose a researcher is studying a population in which 57% of the population has a certain trait. Round your answer to the nearest tenth of a percent if needed. 
The researcher studies a simple random sample of size n = 30. What is the approximate standard deviation of a sampling distribution of the proportion for samples this size? @directrix

daniellelovee · Answer

I got 9 is that right?

daniellelovee · Answer

I dont think thats right I got 9

daniellelovee · Answer

yeah nvm lol it was 9 sorry for asking

daniellelovee · Answer

because I got (57(100-57)/30)

directrix · Answer

Did you take the square root?

daniellelovee · Answer

but my options dont show that

daniellelovee · Answer

yes sorry I forgot to say that

directrix · Answer

What number are you using for the standard deviation of the population?  The copy of the book I'm using does not have options.

daniellelovee · Answer

the formula for standard deviation is sqrtp(100-p)/n

daniellelovee · Answer

because of sampling distribution

daniellelovee · Answer

it just said that formula on my book with an example but the question I really need help on is the other one please

daniellelovee · Answer

http://openstudy.com/study#/updates/54d411d6e4b040c016b70b4b

daniellelovee · Answer

this are the problems with my options