Construct a Confidence Interval For $\mu _ { \mathrm { d } }$

question 98

Multiple Choice

Construct a confidence interval for $\mu _ { \mathrm { d } }$ , the mean of the differences d for the population of paired data. Assume that the
population of paired differences is normally distributed.
-A test of writing ability is given to a random sample of students before and after they completed a formal writing course. The results are given below. Construct a 99% confidence interval for the mean difference
Between the before and after scores. $\begin{array}{llllllllllll}\text { Before } & 70 & 80 & 92 & 99 & 93 & 97 & 76 & 63 & 68 & 71 & 74 \\\hline \text { After } & 69 & 79 & 90 & 96 & 91 & 95 & 75 & 64 & 62 & 64 & 76\end{array}$

• A) \(1.2 < \mu _ { \mathrm { d } } < 2.8\)
• B) \(- 0.2 < \mu _ { \mathrm { d } } < 4.2\)
• C) \(- 0.1 < \mu _ { \mathrm { d } } < 4.1\)
• D) \(- 0.5 < \mu _ { \mathrm { d } } < 4.5\)

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Definitions:

Quantity Supplied

The amount of a good or service that producers are willing and able to offer for sale at a given price level in a given time period.

Equilibrium Price

The point at which the demand for a particular good or service matches its supply, ensuring equilibrium in the market.

Equilibrium Quantity

The quantity of goods or services that is supplied and demanded at the equilibrium price, where the quantity supplied equals the quantity demanded, leading to market stability.

Equilibrium Price

The market price at which the quantity of goods demanded equals the quantity of goods supplied, leading to a stable market condition.