{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

hw3_new_new_solutions

# hw3_new_new_solutions - IEOR 130 Solutions to HW 3 Spring...

This preview shows pages 1–2. Sign up to view the full content.

IEOR 130 Solutions to HW 3 Spring, 2008, Prof. Leachman 1. Using a p-chart, the control limit is . . p n ) p ( p p UCL 04 0 1 3 = + = where Shift # of wafers # of wafers rework UCL Number processed reworked fraction ( p ) 1 500 20 .04 .0663 2 650 39 .06 .0631 3 550 36 .0654 .0651 4 600 18 .03 .0640 Rework was in statistical control during shifts 1, 2 and 4. 2. (a) The sample size is n = 100, and the average range, R-bar is 200.6. From the table in the back of the book, d 2 = 5.015. Hence σ = R-bar / d 2 = 200.6 / 5.015 = 40. Now μ + Z* σ = 150 for some Z, and we are given that 4% fall below the LSL, i.e., Prob. { Z < (150 - μ ) / σ } = 0.04. From the table in the back of the book, Z = -1.75. Hence μ = 150 + 1.75(40) = 220. (b) For bin 3, -1.75 <= Z <= (233-220) / 40 = 0.325. From the table in the back of the book, the probability Z lies in this range is 0.9599 – 0.372 = 0.588. Hence we expect 59 chips per wafer in bin 3. For bin 2, 0.325 <= Z <= (300 – 220) / 40 = 2.0. From the table in the back of the book, the probability Z lies in this range is 0.372 – 0.0228 = 0.349. Hence we expect 35 chips per wafer in bin 2. For bin 1, Z >= 2, which has probability 0.0228. Hence we expect 2 chips per wafer in bin 1.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern