Q 8.121. - Elementary Statistics

Question

Identify the formula for the margin of error for the estimate of a population mean when the population standard deviation is unknown.

Step-by-Step Solution

Answer

$E=t_{\frac{a}{2}}\left(\frac{s}{\sqrt{n}}\right)$

Step 1: Concept

Formula used: Margin of error $E=t_{\frac{a}{2}}\left(\frac{s}{\sqrt{n}}\right)$

Step 2: Explanation

The margin of Error:

The common formula for the margin of error when the standard deviation of the population is unknown: $E=t_{\frac{a}{2}}\left(\frac{s}{\sqrt{n}}\right)$

Step 3: Explanation

Make a variable definition.

• The sample size is $n$
• The sample standard deviation is $s$
• The critical value of $t$ is $t_{\frac{\alpha }{2}}$