By design, a required dimension of a part is 0.575 cm plus or minus 0.008 cm. Assume that the process producing this part is stable with a mean of 0.579 cm and standard deviation of 0.002 cm. The specification limits for this part are
A) 0.554 to 0.596 cm.
B) 0.567 to 0.583 cm.
C) 0.576 to 0.598 cm.
D) 0.572 to 0.584 cm.
E) 0.575 to 0.578 cm.

Question

Quizplus · Accepted Answer

The upper specification limit (USL) can be calculated by adding the upper limit of the required dimension tolerance (+0.008 cm) to the mean of the process (0.579 cm). 
USL = 0.579 + 0.008 = 0.587 cm. 
Similarly, the lower specification limit (LSL) can be calculated by subtracting the lower limit of the required dimension tolerance (-0.008 cm) from the mean of the process (0.579 cm). 
LSL = 0.579 - 0.008 = 0.571 cm. 
Therefore, the specification limits for this part are 0.567 cm to 0.583 cm, which is choice B.

By Design, a Required Dimension of a Part Is 0