The National Assessment of Educational Progress (NAEP) periodally administers tests on different subjects to high school students. In 2000, the grade 12 students in the sample average 301 on the mathematics test; the SD was 30. The likely size of the chance error in the 301 is about.
(a) Can you fill in the blank if a cluster sample of 1,000 students was tested? If so, what is the answer? If not, why not?
(b) Can you fill the blank if a simple random sample of 1,000 students was tested? If so, what is the answer? If not, why not?