Your team performed replicate analyses of a sample and obtained an average 18.54 mM concentration with a relative standard deviation of 4.0%. If you later discover that a systematic error was made by a factor of 2 and the mean concentration should have been 9.27 mM, what is the correct relative standard deviation?

1 answer

(s/mean)*100 = RSD
You know RSD and mean, solve for s, then use s and the same formula with the new mean to solve for new RSD. I think the answer is 8.0%