Answer:
95% Confidence interval for taxi fare: ($20.5,$24.2)
Step-by-step explanation:
We are given the following data set: for fares:
$22.10, $23.25, $21.35, $24.50, $21.90, $20.75, and $22.65
Formula:
[tex]Mean = \displaystyle\frac{\text{Sum of all observations}}{\text{Total number of observation}}[/tex]
[tex]Mean =\displaystyle\frac{156.5}{7} = 22.35[/tex]
95% Confidence interval:
[tex]\bar{x} \pm z_{critical}\frac{\sigma}{\sqrt{n}}[/tex]
Putting the values, we get,
[tex]z_{critical}\text{ at}~\alpha_{0.05} = 1.96[/tex]
[tex]22.35 \pm 1.96(\frac{2.5}{\sqrt{7}} ) = 22.35 \pm 1.85 = (20.5,24.2)[/tex]
