Specifications call for the wall thickness of two-liter

Chapter 6, Problem 7E

(choose chapter or problem)

Specifications call for the wall thickness of two-liter polycarbonate bottles to average 4.0 mils. A quality control engineer samples 7 two-liter polycarbonate bottles from a large batch and measures the wall thickness (in mils) in each. The results are: 3.999, 4.037,  4.116, 4.063, 3.969, 3.955, and 4.091. It is desired to test \(H_0:\mu=4.0\) versus \(H_1:\mu \ne 4.0\).

a. Make a dotplot of the seven values.

b. Should a Student’s t test be used to test \(H_0\)? If so, perform the test. If not, explain why not.

c. Measurements are taken of the wall thicknesses of seven bottles of a different type. The measurements this time are: 4.004, 4.225, 3.924, 4.052, 3.975, 3.976, and 4.041. Make a dotplot of these values.

d. Should a Student’s t test be used to test \(H_0:\mu = 4.0\) versus \(H_1:\mu \ne 4.0\)? If so, perform the test. If not, explain why not.

Equation Transcription:

Text Transcription:

H_0:mu=4.0

H_1:mu{not=}4.0

H_0

H_0:mu=4.0

H_1:mu{not=}4.0