Q.7 - The Practice of Statistics for AP

Question

Unlisted numbers: A telemarketing firm in Los Angeles uses a device that dials residential telephone numbers in that city at random. Of the first $100$ numbers dialed, $48\%$ are unlisted. This is not surprising because $52\%$ of all Los Angeles residential phones are unlisted.

Step-by-Step Solution

Answer

The value of

Statistics $\hat{p}=48\%=0.48$.

Parameter $p=52\%=0.52$.

Step 1: Given Information

Of the first $100$ numbers dialed, 48% are unlisted. This is not surprising because $52\%$of all Los Angeles residential phones are unlisted. 

Step 2: Explanation

Of the first $100$ numbers dialed, $48\%$ are unlisted.

A parameter is a descriptive measure for a population, while a statistic is a descriptive measure for a sample.

Statistic

The sample proportion is represented by $\hat{p}$ :

$$\begin{gathered} \hat{p}=48\% \\ =0.48 \end{gathered}$$

Step 3: Explanation

$52\%$ of all Los Angeles residuals phones are unlisted.

A parameter is a descriptive measure for a population, while a statistic is a descriptive measure for a sample.

Parameter

The population proportion is represented by $p$ :

$$\begin{gathered} p=52\% \\ =0.52 \end{gathered}$$