Case Study Quality Management Toyota

Answers to the case questions  Name: 吳菲樂 105363127 Case name: Quality Management !oyota !oyota Question 1: "# the s$eci#ication is such that no washer shoul% &e greater than 2'( milimeters) assuming that the thic*nesses are %istri&ute% normally) what #raction o# the out$ut is e+$ecte% to  &e greater than this thic*ness, Answer: !he -raction that is e+$ecte% to &e greater than this thic*ness is 1,844098808.  Question 2: "# there are an u$$er an% lower s$eci#ication) where the u$$er limit is 2'( an% the lower lower limit is 1'() what #raction o# the out$ut is e+$ecte% to &e out o# the $rocess, Answer: !he #raction to &e e+$ecte% to &e out o# the $rocess is 2,208517%  Question 3: /hat is the C  pk   #or the $rocess , Answer: !he C  pk   #or the $rocess is 0,695689.  Question (: /hat woul% &e the C  pk   #or the $rocess i# it were centere% &etween the s$eci#ication limits assume the $rocess stan%ar% %eiation is the same, Answer: !he the C  pk   #or the $rocess i# it were centere% &etween the s$eci#ication limits woul%  &e 0,795073574.  Question 5: /hat $ercentage o# out$ut woul% &e e+$ecte% to &e out o# tolerance i# the $rocess were centere%, Answer: !he $ercentage o# out$ut to &e e+$ecte% to &e out o# tolerance i# the $rocess were centere% is 1,706888%  Question 6: et u$  X   an% range control charts #or the current $rocess' Assume the o$erators will ta*e sam$les 10 washers at a time' Answer: ´

A2 =0.31 D3 =0.22 D4 =1.78 Lower limit  X  41'761 Upper limit  X  42'16( Lower limit R= 0.143 Upper limit R=1.157  Question 7: lot the %ata on your control charts' oes the current $rocess a$$ear to &e in control, Answer: ´

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control c!rt "#$!r LL &"#$!r'#$!r UL

control c!rt

R LL R#$!r UL

Accor%ing to the control charts a&oe) the $rocess seems to &e in control) as the %ata is still con#ine% &etween the u$$er an% lower limits  Question : "# the $rocess coul% &e im$roe% so that the stan%ar% %eiation were a&out only '10 milimeter) what woul% &e the &est that coul% &e e+$ecte% with the $rocesses relatie to #raction %e#ectie, Answer: "# the $rocess coul% &e im$roe% so that the stan%ar% %eiation were a&out only '10 milimeter) then %e &est that coul% &e e+$ecte% with the $rocesses relatie to #raction %e#ectie woul% &e 573 %e#ects in eery 1 &illion washers'