Question

Prob-4 Composites are materials that are made by embedding a fiber, such as glass or carbon, inside a matrix, such as a metal or a ceramic. Composites are used in engineering structures, and their degradation when subjected to wheather conditions is an important issue.. In an experiment to investigate the effect of the moisture on a certain kind of composite, the weight gans of collection ofn-21 samples of composite subjected to water diffusion were obta ned. The sample mean is r0.42% with ล smple std. of s-004% Can we 90% confident from the results of this experiment that the average weight gain for composites of this kind is sm aller tha О43%?

Answer 1

soiu^ion standa-nd deviation (s)s 。. 04 Meon IA) = 0.41, Bgud lng .fab le. 군 o, 8248 f=