Cholesterol levels are measured on a random sample of 1k people. A second survey was repeated in the same population, but the sample size tripled to 4k. What happens to the standard deviation?

Answer 1

The standard deviation will not vary as a function of sample size. The standard error which is standard deviation / square root of sample size, decreases with increasing sample size.

Answer 2

I am confused by the statement that it tripled from 1K to 4K (that's quadrupled) but that aside, if the population variance is assumed to be known and we are going with the formula of population standard deviation / sqrt (n) = the standard deviation of the sample; then it would be half of what it was before.