Question

A student polls his school to see if students in the school district are for or against the new legislation regarding school uniforms. She surveys 488 students and finds that 222 are against the new legislation.

Calculate the EPB. Use a 90% Confidence Level. Fill in the blank, round to three decimal places.

Answer 1

The sample proportion here is computed as:
p = x/n = 222/488 = 0.4549

From standard normal tables, we have:
P( -1.645 < Z < 1.645) = 0.9

Therefore the confidence interval here is obtained as:

This is the required 90% confidence interval for the true population propotion of students who are against the new legislation here.