Question

Confidence interval proportion. You are given the following information about a sample: the number who answered yes = 300, n = 850. What is the bound of error for a 90% confidence interval?

Answer 1

To calculate the bound of error for a confidence interval, use the formula: Bound of Error = Z * sqrt(p*(1-p)/n), where Z is the critical value, p is the sample proportion, and n is the sample size. In this case, the bound of error for a 90% confidence interval is 0.0349.

Step-by-step explanation:

To calculate the bound of error for a confidence interval, we can use the formula:

Bound of Error = Z * sqrt(p*(1-p)/n)

where Z is the critical value for the desired confidence level, p is the sample proportion, and n is the sample size.

In this case, the sample proportion is 300/850 = 0.3529 and the desired confidence level is 90%.

The critical value for a 90% confidence level is 1.645. Plugging these values into the formula, we get:

Bound of Error = 1.645 * sqrt(0.3529 * (1-0.3529)/850) = 0.0349.

Therefore, the bound of error for a 90% confidence interval is 0.0349.