For the Following Data, What Is the Mean of the Difference

question 9

Multiple Choice

For the following data, what is the mean of the difference scores? $$\begin{array} { | r r } \hline { \text { Before } } & \text { After } \\\hline 160 & 153 \\\hline 125 & 124 \\\hline 142 & 136 \\\hline 187 & 167 \\\hline\end{array}$$

• A) 8.50
• B) 5.00
• C) 4.26
• D) 11.33

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Definitions:

Substitutes

Goods or services that can be used in place of each other, where an increase in the price of one leads to an increase in the demand for the other.

Demand

The measure of a good or service that patrons are eager and able to procure, across various pricing, throughout a certain duration.

Price Ceiling

A legally established maximum price for a good, or service. Normally set at a price below the equilibrium price.

Sellers

Individuals or entities that offer goods or services for sale in the market, playing a key role in determining the supply conditions.