We Are Interested in Comparing the Average Supermarket Prices of Two

question 81

Short Answer

We are interested in comparing the average supermarket prices of two leading colas. Our sample was taken by randomly selecting eight supermarkets and recording the price of a six-pack of each brand of cola at each supermarket. The data are shown in the following table: $\begin{array}{c}\text { Price }\\\begin{array}{c|cc|c}\text { Supermarket } & \text { Brand 1 } & \text { Brand 2 } & \text { Difference } \\\hline 1 & \$ 2.25 & \$ 2.30 & \$-0.05 \\2 & 2.47 & 2.45 & 0.02 \\3 & 2.38 & 2.44 & -0.06 \\4 & 2.27 & 2.29 & -0.02 \\5 & 2.15 & 2.25 & -0.10 \\6 & 2.25 & 2.25 & 0.00 \\7 & 2.36 & 2.42 & -0.06 \\8 & 2.37 & 2.40 & -0.03 \\\hline & \mathrm{x}_{1}=2.3125 & \mathrm{x}_{2}=2.3500 & \mathrm{~d}=-0.0375 \\& \mathrm{~s}_{1}=0.1007 & \mathrm{~s}_{2}=0.0859 & \mathrm{~s} \mathrm{~d}=0.0381\end{array}\end{array}$

Find a $98 \%$ confidence interval for the difference in mean price of brand 1 and brand 2 .
A) $0.0375 \pm 0.0404$
B) $0.0375 \pm 0.1393$
C) $0.0375 \pm 0.0471$
D) $0.0375 \pm 0.0347$

• A) \(0.0375 \pm 0.0404\)
• B) \(0.0375 \pm 0.1393\)
• C) \(0.0375 \pm 0.0471\)
• D) \(0.0375 \pm 0.0347\)

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Definitions:

Period Of Decline

A phase in which something, such as a business, economy, or physical condition, experiences a decrease in quality, quantity, or importance.

Negative Feedback

Criticisms or evaluations indicating a discrepancy between expected and actual performance, intended to prompt improvement.

Positive Feedback

Encouraging or affirmative information provided in response to an action or behavior, intended to reinforce and promote repetition of the behavior.

Systemic Approaches

Strategies or methods that consider the complex interrelationships within systems, such as in families, organizations, or ecosystems, to address issues or implement changes.