91Ó°ÊÓ

$percentile=\frac{numberofdatavaluesthatarelessthantheindividual\text{'}sdatavalue}{totalnumberofdatavalues}×100\%$

The dot plot shows that $26$ of the $40$ dots to the left of the red dot have a price below $\$234000$ which is the certain value linked with the red dot. This means that $26$ of the $40$ dwellings in the sample have a price below $\$234000$ The percentile is calculated by dividing the number of data values less than the individual's data value by the total number of data values.

$percentile=\frac{numberofdatavaluesthatarelessthantheindividual\text{'}sdatavalue}{totalnumberofdatavalues}×100\%$

$$\begin{gathered} =\frac{26}{40}×100 \\ =65\% \end{gathered}$$

As a result, the percentile associated with the red dot is the ${65}^{th}$ percentile.

$$\begin{gathered} z=\frac{x−\mathrm{μ}}{\mathrm{σ}} \\ =\frac{234000−203388}{87609} \\ =0.35 \end{gathered}$$

The $z-$score displays how many standard deviations a value deviates from the mean, with a negative $z-$score indicating a value below the mean and a positive $z-$score indicating a value above the mean.

The house's sales price of $\$234000$ is $0.35$standard deviations more than the mean selling price of $\$203388$