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2010-10-27_014123_As_a_quality_analyst_you

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					            A          B           C           D           E             F              G            H
 1   As a quality analyst you are also responsible for controlling the weight of a box of cereal. The Operations Manager ask
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 3   Your   report should indicate the following along with valid justifications of your answers:
 4   a.     The control limits of the weights of the boxes.
 5   b.     Nonrandom patterns or trends, if any.
 6   c.     If the process is in control.
 7   d.     The appropriate action if the process is not in control.
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10                   Sample        Box 1        Box 2      Box 3   Sample Means Maximum Minimum
11                        1        6.300        6.280      6.260           6.280   6.300   6.260
12                        2        6.320        6.320      6.330           6.323   6.330   6.320
13                        3        6.290        6.330      6.360           6.327   6.360   6.290
14                        4        6.300        6.290      6.340           6.310   6.340   6.290
15                        5        6.295        6.315      6.390           6.333   6.390   6.295
16                        6        6.292        6.319      6.330           6.314   6.330   6.292
17                        7        6.289        6.323      6.400           6.337   6.400   6.289
18                        8        6.286        6.327      6.471           6.361   6.471   6.286
19                        9        6.283        6.331      6.498           6.371   6.498   6.283
20                      10         6.280        6.335      6.525           6.380   6.525   6.280
21                      11         6.277        6.339      6.390           6.335   6.390   6.277
22                      12         6.274        6.343      6.400           6.339   6.400   6.274
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24                See all the other sheets in this file.
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26                (a) The control limits are: (a) For Mean weight, LCL = 6.3087 ounces, UCL = 6.3696 ounces and (b) For Range,
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28                (b) At the time measurements were taken on the 5th through 9th samples, the mean weights and the range
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30                (c ) The process is not in control since we see points lying outside the control limits in both x-bar chart and R
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32                (d) Corrective action in terms of resetting the machine is required. Trials should be run and again more samp
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     A       B           C           D           E              F              G            H
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59       See all the sheets for the calculations and tables. The process is in statistical control.
                          I            J          K           L          M          N          O          P          Q
                Operations Manager asks you to identify the ways in which statistical quality control methods can be applied to the weigh
 of cereal. The 1
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                10 Sample Range
                11            0.040
                12            0.010
                13            0.070
                14            0.050
                15            0.095
                16            0.038
                17            0.111
                18            0.185
                19            0.215
                20            0.245
                21            0.113
                22            0.126
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UCL = 6.3696 ounces and (b) For Range, LCL = 0.0324 ounes, UCL = 0.1964 ounce
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mples, the mean weights and the range of weights appears to have been increasing in a somewhat linear pattern. It appears that the filling
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                in
 control limits 30 both x-bar chart and R chart.
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                run
 als should be 32 and again more samples drawn to check if the process has come under control.
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     I   J   K   L   M   N   O   P   Q
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                      R           S          T           U          V          W           X           Y           Z
ds can be applied to the weights of the boxes. Provide your recommendations to the Operations Manager in a report. Using the data pro
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ttern. It appears that the filling machine has gradually gone off setting during this period. This is the only non-random variation observed
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     R   S   T   U   V   W   X   Y   Z
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                     AA         AB         AC         AD         AE       AF
nager in a report. Using the data provided create Xbar and R charts.
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nly non-random variation observed at the time of taking the 12 measurements.
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                                 Control Chart Calculations
              6.39



              6.38



              6.37                                                 UCL



              6.36
Sample Mean




              6.35
                                                                               XBar
                                                                               LCL-X
              6.34                                                 XBar        Center-X
                                                                               UCL-X

              6.33



              6.32



              6.31
                                                                   LCL


               6.3
                     0   2   4            6           8       10          12
                                  Control Chart Calculations
                0.3




               0.25




                0.2
                                                                    UCL
Sample Range




                                                                                Range
               0.15
                                                                                LCL-R
                                                                                Center-R

                                                                    RBar        UCL-R

                0.1




               0.05

                                                                    LCL



                 0
                      0   2   4            6           8       10          12
Number        XBar       Range       LCL-R       Center-R    UCL-R       LCL-X       Center-X    UCL-X
          1    6.323333       0.01    0.032365    0.114364    0.196362    6.308731    6.339152    6.369572
          2    6.326667       0.07    0.032365    0.114364    0.196362    6.308731    6.339152    6.369572
          3         6.31      0.05    0.032365    0.114364    0.196362    6.308731    6.339152    6.369572
          4    6.333333      0.095    0.032365    0.114364    0.196362    6.308731    6.339152    6.369572
          5    6.313667      0.038    0.032365    0.114364    0.196362    6.308731    6.339152    6.369572
          6    6.337333      0.111    0.032365    0.114364    0.196362    6.308731    6.339152    6.369572
          7    6.361333      0.185    0.032365    0.114364    0.196362    6.308731    6.339152    6.369572
          8    6.370667      0.215    0.032365    0.114364    0.196362    6.308731    6.339152    6.369572
          9         6.38     0.245    0.032365    0.114364    0.196362    6.308731    6.339152    6.369572
         10    6.335333      0.113    0.032365    0.114364    0.196362    6.308731    6.339152    6.369572
         11        6.339     0.126    0.032365    0.114364    0.196362    6.308731    6.339152    6.369572
                    A                       B            C          D           E      F      G        H
 1   Control Chart Calculations
 2                                                              Control Chart Factors Table.
 3                      Data                                 Subgroup size D3        D4    A2
 4   Sample/Subgroup Size                          12                     2      0 3.267 1.880
 5                                                                        3      0 2.575 1.023
 6           R Chart Intermediate Calculations                            4      0 2.282 0.729
 7   RBar                                 0.114363636                     5      0 2.114 0.577
 8   D3 Factor                                   0.283                    6      0 2.004 0.483
 9   D4 Factor                                   1.717                    7 0.076 1.924 0.419
10                                                                        8 0.136 1.864 0.373
11               R Chart Control Limits                                   9 0.184 1.816 0.337
12   Lower Control Limit                0.032364909                      10 0.223 1.777 0.308
13   Center                             0.114363636                      11 0.256 1.744 0.285
14   Upper Control Limit                0.196362364                      12 0.283 1.717 0.266
15                                                                       13 0.307 1.693 0.249
16          XBar Chart Intemediate Calculations                          14 0.328 1.672 0.235
17   Average of Subgroup Averages         6.339151515                    15 0.347 1.653 0.223
18   A2 Factor                                   0.266                   16 0.363 1.637 0.212
19   A2 Factor * RBar                     0.030420727                    17 0.378 1.622 0.203
20                                                                       18 0.391 1.609 0.194
21             XBar Chart Control Limits                                 19 0.404 1.596 0.187
22   Lower Control Limit               6.308730788                       20 0.415 1.585 0.180
23   Center                            6.339151515                       21 0.425 1.575 0.173
24   Upper Control Limit               6.369572242                       22 0.435 1.565 0.167
25                                                                       23 0.443 1.557 0.162
26                                                                       24 0.452 1.548 0.157
27                                                                       25 0.459 1.541 0.153
28                                                                                 value Factornot available. Possible erro
                                                                                          value value not available. in sam
                                                                         26 Factor Factornot available. Possible errorPossib
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Factor value not available. Possible error in sample/subgroup size.
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sible error in sample/subgroup size.

				
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posted:9/19/2012
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