Answer:
421
Step-by-step explanation:
Margin of error = E = 0.04
Confidence Level = 90%
z value associated with this confidence level = z = 1.645
Previous estimate of population proportion = p = 0.54
q = 1 - p = 1 - 0.54 = 0.46
The formula of Margin of Error for population proportion is:
[tex]E=z\sqrt{\frac{pq}{n}}[/tex]
Here, n is the sample size.
Re-arranging the equation for n and using the values we get:
[tex]n=(\frac{z}{E})^{2} \times pq\\\\ n = (\frac{1.645}{0.04})^{2} \times 0.54 \times 0.46\\\\ n = 421[/tex]
Thus the minimum sample size required to estimate the proportion of adults who have high speed internet access is 421
