Question Number 59098 by Huygens last updated on 04/May/19
$${A}\:{sample}\:{of}\:\mathrm{20}\:{cigarettes}\:{is}\:{tested}\:{to}\:{determine}\:{nicotine}\:{vomtent} \\ $$$${and}\:{the}\:{average}\:{value}\:{observed}\:{was}\:\mathrm{1}.\mathrm{2}{mg}.{Compute} \\ $$$${a}\:\mathrm{99}\:{percentage}\:{two}−{sided}\:{confidence}\:{interval} \\ $$$${or}\:{the}\:{mean}\:{nicotine}\:{content}\:{if}\:{it}\:{is}\:{known}\:{that}\:{the}\:{standard}\:{deviation}\:{of}\:{a}\:{cigarette}'{s}\: \\ $$$${nicotine}\:{content}\:{is}\:\mathrm{0}.\mathrm{2}{mg}. \\ $$