A Researcher Is Estimating the Average Difference Between Two Population

Multiple Choice

A researcher is estimating the average difference between two population means based on matched-pairs samples.She gathers data on each pair in the study resulting in: $$\begin{array} { | l | l | l | } \hline \text { Pair } & \text { Group 1 } & \text { Group 2 } \\\hline 1 & 10 & 12 \\\hline 2 & 8 & 9 \\\hline 3 & 11 & 11 \\\hline 4 & 8 & 10 \\\hline 5 & 9 & 12 \\\hline\end{array}$$ Assume that the data are normally distributed in the population.To obtain a 90% confidence interval, the table t value would be _______.

A) 1.86
B) 1.397
C) 1.533
D) 2.132
E) 3.346