posted by Yesenia on .
How heavy a load (pounds) is needed to pull apart pieces of Douglas fir 4 inches long and 1.5 inches square? Here are data from students doing a laboratory exercise:
22565 28373 25826 26468 27508
23401 24998 32436 25405 29235
29679 33661 27775 28517 30371
27793 32527 32748 26052 29398
We are willing to regard the wood pieces prepared for the lab session as an SRS of all similar pieces of Douglas fir. Suppose that the strength of pieces of wood like these follows a Normal distribution with standard deviation 3100 pounds.
Give a 95% confidence interval for the mean load required to pull the wood apart (give your answer with three decimal places).
95% confidence interval for the mean load is__________ to__________ .