The compressive strength of parts made from a composite material are known to be nearly normally distributed. A scientist, using the testing device for the first time, obtains the tensile strength (psi) of 20 specimens

\[\begin{array}{rlllllllll}95 & 102 & 105 & 107 & 109 & 110 & 111 & 112 & 114 & 115 \\134 & 135 & 136 & 138 & 139 & 141 & 142 & 144 & 150 & 155\end{array}\]

shown in Figure 7.12. Should the scientist report the 95\% confidence interval based on the \(t\)-distribution? Explain your reasoning.

Data From Figure 7.12

Transcribed Image Text:

Figure 7.12 90 100 110 120 130 140 150 160 Dot diagram of tensile strength Strength (psi)