Questions: A magazine provided results from a poll of 1500 adults who were asked to identify their favorite pie. Among the 1500 respondents, 12% chose chocolate pie, and the margin of error was given as ± 5 percentage points. What values do p̂, q̂, n, E, and p represent? If the confidence level is 95%, what is the value of α?
The value of p̂ is the sample proportion.
The value of q̂ is found from evaluating 1-p̂.
The value of n is the sample size.
The value of E is the margin of error.
The value of p is the population proportion.
Transcript text: A magazine provided results from a poll of 1500 adults who were asked to identify their favorite pie. Among the 1500 respondents, $12 \%$ chose chocolate pie, and the margin of error was given as $\pm 5$ percentage points. What values do $\hat{p}, \hat{q}, n, E$, and $p$ represent? If the confidence level is $95 \%$, what is the value of $\alpha$ ?
The value of $\hat{p}$ is
The value of $\hat{q}$ is
The value of $n$ is
The value of $E$ is
The value of $p$ is
found from evaluating $1-\hat{\mathbf{p}}$.
the sample proportion.
the sample size.
the population proportion.
the margin of error.
Solution
Solution Steps
Step 1: Calculate the Sample Proportion ($\hat{p}$)
To calculate the sample proportion $\hat{p}$, divide the number of respondents with the characteristic by the total sample size $n$.
$$\hat{p} = \frac{180}{1500} = 0.12$$
Step 2: Determine the Complement of the Sample Proportion ($\hat{q}$)
The complement of the sample proportion $\hat{q}$ is calculated as $1 - \hat{p}$.
$$\hat{q} = 1 - \hat{p} = 1 - 0.12 = 0.88$$
Step 3: Identify the Sample Size ($n$)
The sample size $n$ is directly identified from the information provided and is 1500.
Step 4: Note the Margin of Error ($E$)
The margin of error $E$ is given in the problem statement as 0.05.
Step 5: The Population Proportion ($p$)
The population proportion $p$ is typically what one aims to estimate and is not directly calculated but inferred from $\hat{p}$ and $E$.
Step 6: Calculate the Significance Level ($\alpha$)
To find the significance level $\alpha$, subtract the confidence level (expressed as a decimal) from 1.
$$\alpha = 1 - \text{Confidence Level} = 1 - 0.95 = 0.05$$
Final Answer:
The sample proportion $\hat{p}$ is 0.12, the complement $\hat{q}$ is 0.88, the sample size $n$ is 1500, the margin of error $E$ is 0.05, and the significance level $\alpha$ is 0.05.