Exhibit 11-7
The results of a recent poll on the preference of shoppers regarding two products are shown below.
$$\begin{array}{l}
&&\text { Shoppers Favoring }\
\text { Product } & \text { Shoppers Surveyed } & \text { This Product } \
\text { A } & 800 & 560 \
\text { B } & 900 & 612
\end{array}$$
-Refer to Exhibit 11-7. The 95% confidence interval estimate for the difference between the populations favoring the products is
A) -0.024 to 0.064
B) 0.6 to 0.7
C) 0.024 to 0.7
D) 0.02 to 0.3

Question

Exhibit 11-7
The results of a recent poll on the preference of shoppers regarding two products are shown below.
 $$\begin{array}{l}
&&\text { Shoppers Favoring }\
\text { Product } & \text { Shoppers Surveyed } & \text { This Product } \
\text { A } & 800 & 560 \
\text { B } & 900 & 612
\end{array}$$
-Refer to Exhibit 11-7. The 95% confidence interval estimate for the difference between the populations favoring the products is
A) -0.024 to 0.064
B) 0.6 to 0.7
C) 0.024 to 0.7
D) 0.02 to 0.3

Quizplus · Accepted Answer

The confidence interval for the difference in proportions is calculated using the formula for the difference between two independent proportions. The interval is calculated as (p1 - p2) ± Z * sqrt((p1(1-p1)/n1) + (p2(1-p2)/n2)), where p1 and p2 are the sample proportions, n1 and n2 are the sample sizes, and Z is the Z-value for 95% confidence. The calculations yield an interval of approximately -0.024 to 0.064.

Exhibit 11-7 the Results of a Recent Poll on the Preference

Exhibit 11-7
the Results of a Recent Poll on the Preference