5. The results of an inspection of DNA samples taken over the past 10 days are g

Question

5. The results of an inspection of DNA samples taken over the past 10 days are given below. Sample size is 50. Day # of defectives 1 2 3 4 5 6 7 8 9 10 (a) Determine the fraction defective p of the p chart. Please give the formula and at least one step of calculation for full credit. (6 points) (b) Determine the pof the p chart. Please give the formula and at least one step of calculation for full credit. (6 points) (c) Determine the 3-sigma upper control limit and the 3-sigma lower control limit of the p chart. For each control limit, provide at least one step of calculation and the correct answer for full credit. (8 points)

Explanation / Answer

a) Fraction defective (p-bar) = Number of defectives/Number of samples = (2+1+3+2+.............+2)/(10*50) = 0.044

b) sigma = sqrt(p-bar*(1-p-bar)/n) = sqrt(0.044*(1-0.044)/50) = 0.029

c) UCL = p-bar + z*sigma

LCL = p-bar - z*sigma

z = 3

UCL = 0.044 + 3*0.029 = 0.131

LCL = 0.044 - 3*0.029 = -0.043. As it cannot be negative, hence 0

Related Questions

Navigate

• Browse (All)
• Browse 5
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.