use the quick method to estimate the margin of error for conclusions about all 620 adults with 95% confidence
To estimate the margin of error for conclusions about all 620 adults with 95% confidence, you can use the quick formula:
Margin of Error = (Critical Value) * (Standard Error)
1. The critical value is the number of standard deviations corresponding to the desired level of confidence. For a 95% confidence level, the critical value is approximately 1.96.
2. The standard error represents the variability in the sample mean. It is calculated by dividing the standard deviation of the population by the square root of the sample size (n). However, if the population standard deviation is unknown, you can use the sample standard deviation as an estimate.
So, the formula for estimating the margin of error becomes:
Margin of Error = 1.96 * (Standard Deviation / Square Root of Sample Size)
Keep in mind that this assumes you have a random sample that is representative of the population you are trying to make conclusions about. If the sample is not representative or if there are other sources of bias, the margin of error calculation may not accurately reflect the true variability.
Also, it's important to note that this method assumes a large enough sample size that satisfies the Central Limit Theorem, typically a sample size of at least 30. If your sample size is smaller, you may need to use different methods to estimate the margin of error.