Question

Assume that a random sample is used to estimate a population proportion p. Find the margin of error E that corresponds to the given statistics and confidence level.
n = 550, x = 220, 95% confidence
The margin of error E = ________.
​(Round to four decimal places as​ needed.)

Answer 1

Answer: 0.04

Step-by-step explanation:

Population Proportion (p) = X/N

x=220

n=550

p= 220/550= 0.4

q= 1 - p = 1- 0.4 = 0.6

margin of error e = z * sqrt [p(q/n)]

To determine z:

Confidence = 95% or 0.95

Significance level = s = 1- 0.95 = 0.05

Critical z value = s/2

0.05/2 = 0.025.

From z table, 0.025 = 1.96

Margin or Error e= 1.96 * Sqrt[0.4( 0.6/550)]

e=0.04