Margin of Error
Z-Score vs T-Score
Z-Score
Z-Score’s formula
$$z = \frac{X - \mu}{\sigma}$$
where X = sample mean, $\mu$ = population means, $\sigma$ = population standard deviation.
Also, we use Z Score when sample size >= 30 or we know the population’s mean dna SD.
T-Score
T-Score T-Score’s formula $$T = \frac{X - \mu}{s/ \sqrt{n}}$$ where X = sample mean, $\mu$ = population mean, s = sample standard deviation, and n = sample size.
Margin of Error
They are two ways to find the margin of error $$ME = Z \frac{\sigma}{\sqrt{n}}$$ Or if we know the population proportion $$ME = Z \sqrt{\frac{p(1 - p)}{n}}$$