A Stratified Sample of Size $n=300$ Is to Be Taken from a Population of Size

Short Answer

A stratified sample of size $n=300$ is to be taken from a population of size $N=30,000$ which consists of four strata for which $N_{1}=10,000, N_{2}=5,000, N_{3}=8,000, N_{4}=7,000, \sigma_{1}=15, \sigma_{2}=25, \sigma_{3}=20$ and $\sigma_{4}=30$ . How large a sample must be taken from each stratum if the allocation is to be
-optimum?