Lumber intended for building houses and other structures must be monitored for strength. The measurement of strength (pounds per square inch) for 61 specimens of Southern Pine (Source:

U.S. Forest Products Laboratory) yielded 4001 3927 3048 4298 4000 3445 4949 3530 3075 4012 3797 3550 4027 3571 3738 5157 3598 4749 4263 3894 4262 4232 3852 4256 3271 4315 3078 3607 3889 3147 3421 3531 3987 4120 4349 4071 3686 3332 3285 3739 3544 4103 3401 3601 3717 4846 5005 3991 2866 3561 4003 4387 3510 2884 3819 3173 3470 3340 3214 3670 3694 Using MINITAB, the sequence of choices produces a rather complete summary of the data. It includes the output on page 79.

(a) Use this output to identify a departure from a bell-shaped pattern.

(b) MINITAB uses a slightly different scheme to determine the first and third quartiles, but the difference is not of practical importance with large samples. Calculate the first quartile using the definition in this book and compare with the value in the output.