Final answer:
To find the margin of error for a 95% confidence interval, calculate the critical value associated with a 95% confidence level and use it in the margin of error formula.
Step-by-step explanation:
To find the margin of error for a 95% confidence interval, you need to calculate the critical value associated with a 95% confidence level. The critical value is based on the standard normal distribution (Z-distribution) and can be found using a calculator or a Z-table. For a 95% confidence level, the critical value is approximately 1.96.
Once you have the critical value, you can calculate the margin of error by multiplying the critical value by the standard deviation divided by the square root of the sample size. The formula for margin of error is: Margin of Error = Critical Value * (Standard Deviation / √(Sample Size))
For example, if you have a sample size of 100 and a standard deviation of 10, the margin of error would be 1.96 * (10 / √100) = 1.96 * 1 = 1.96.