Answer: 16590
Step-by-step explanation:
The formula we use to find the sample size is given by :-
, where p = prior estimate of population proportion.
= Critical z-value (Two- tailed)
E= Margin of error .
Let p be the population proportion of cyanobacteria.
Given : E = 0.01
Critical value for 99% confidence interval :
If Ian does not want to rely on previous knowledge , then we assume p=0.5 because the largest standard error is at p=0.5.
Now, the required sample size =
Required sample size = 16590