SCM 352 ASSESSMENT 3 STUDENT ID ______

I. The McWidget company is about to begin production of a new product. Their machine will produce the item at a rate of 200 units a day. 80 units will be used daily to assemble the final product. The McWidget does work 5 days a week, 50 weeks a year. McWidget’s production manager estimates that it will take almost a full day to get the machine ready for a production run, at a cost of $60. Inventory holding cost will be two dollars a year.

1. What production quantity should be used to minimize total annual cost? D = 80*5*50 = 20000, H = 2, S = 60, p = 200, d = 80 , EOQ = SQRT(2*S*D*p/H*(p-d))

EOQp = SQRT(2*60*20000*200/2*(200-8)) = 1414.214

Production Quantity = ___1414______

2. What is the length of a production in days? tp = EOQp/p

tp = 1414/200 = 7.07

Time in production = ____7.07______

3. During production, at what rate will inventory buildup?

p-d = 200 – 80 = 120

Rate of inventory buildup = _____120 per day______

4. Can McWidget run another job between runs of the new product? A minimum of 10 days will be needed. Will there be enough time?

Circle Yes or No and explain your choice. Qmax = EOQp*(p-d)/p = 1414*120/200 = 848.4 ti = Qmax/d = 848/120 = 10.6 Time available for another job = ti – LT = 10.6 – 1 = 9.6 This is .4 days less than the minimum time needed for another job. Demand for bunny tracks ice cream at the Swedish Ice Cream Dairy can be approximated by a normal distribution with a mean of 3 gallons per week and a standard deviation of .5 gallons per week. The new manager desires a service level of 97%. Lead time is 4 days and the dairy is open seven days a week If an ROP model is used, what ROP would be consistent with the desired service level? (Hint: Use weeks as the unit of measure.)

ROP = 3*(4/7) + 1.89*SQRT(4/7)*.5 = 2.428639

Reorder Point = _____2.5 gallons______

II. K jewelry store buys rings with semiprecious stones. Their supplier quotes a price of about $88 per ring for quantities of 60 rings a more, $90 per ring for orders of 40 to 59 nine stones, and $100 per stone for lesser quantities. The jewelry store is open for business 220 days per year. Ring sales are 8 rings per day, and ordering cost is $48. If annual carrying cost are 30% of unit cost, what is the optimal order size?

EOQ26.40 = SQRT(2*48*1760/26.40) = 80 > 60

Optimal Order Size ______80______

III. Activities, expected completion times, variances, and precedents relationships for the major activities of an R&D project are depicted in the following table. Determine the probability that project completion time will be less than 50 weeks.

Mean Completion Time Precedence Activity Completion Time Variance Relationship A 16 .69 --- B 5 0 --- C 10 .25 B D 11 .69 A E 18 .25 B F 14 .36 C G 24 .11 D H 26 .11 E I 12 .11 F J 0 0 G,H,I Probability that the project completion time is less the 50 = _.2061*1*.9525 = .1963

Path 1 A,D,G,J 51 1.4884 1.22 (50-51)/1.22 .2061 Path 2 B,C,F,I, J 41 .9225 .85 (50-41)/.85 1 Path 3 B,E,H, J 49 .36 .60 (50-49)/.60 .9525

IV. Chuck’s Custom Bikes (CCB) builds racing bikes to customer order. CCB has landed a contract with a mysterious New York lawyer (Mr. T). Relevant data are shown below. The complication is that Mr. T. wants delivery in 36 days or he will impose a penalty of $375 for each day his bike is late.

Activity Normal Precedence Available Days Crash Completion Relationship Crash Days Cost Time(days) K 9 -- 2 $42 L 7 K 1 $15 N 5 K 2 $15 M 4 L 2 $33 J 6 N 1 $15 Q 5 M,J 2 $22 P 8 Q 0 -- Y 7 Q 2 $18 Z 6 P 1 $19 T 1 Y 1 $12

P L M Z T K Q N J Y

Path 1: (K,L,M,Q,P,Z) 39

Path 2: (K,N,J,Q,P,Z) 39

Path 3: (K,L,M,Q,Y,T) 33

Path 4: (K,N,J,Q,Y,T) 33

Day ACTIVITY(S) TO CRASH CRASH COST 1 Z 19

2 Q 22

3 Q 22

IV( 25 PTS.). The Elector Static Company assembles electrostatic copiers. The total assembly time is 40 minutes. After the first copier comes off the assembly line there are 410 minutes of work time available for the work day. Furthermore, the production schedule requires that 40 units be completed as output from the assembly line each day. The task, task times and precedence relationships are given in the table below

Task Time Task that Task (minutes) must precede A 4 --- B 2 A C 5 B D 5 A E 4 D F 3 C,E G 5 F H 2 F I 10 G,H a) ( 3 PTS.) Determine the cycle time. Cycle time = ____410/39 = 10.51______b) ( 2 PTS.) Determine the theoretical minimum number of work stations Theoretical minimum number of stations = _____[40/10.51} = 4______c) (15 PTS.)Assign task to work stations using shortest task time rule. Work Station Available Task Eligible Task Selected Task Idle Time

1 A A A 6.51 B,D B,D B 4.51 C,D

2 C,D C,D C 5.51 D D D .51 E

3 E E E 6.51 F F F 3.51 G,H H H 1.51 G

4 G G G 5.51 I

5 I I I 10.51

Areas under the standardized normal curve, from –∞ to + z z .00 .01 .02 .03 .04 .05 .06 .07 .08 .09 .0 ...... 5000 .5040 .5080 .5120 .5160 .5199 .5239 .5279 .5319 .5359 1 .. .5398 .5438 .5478 .5517 .5557 .5596 .5636 .5675 .5714 .5753 .2 ...... 5793 .5832 .5871 .5910 .5948 .5987 .6026 .6064 .6103 .6141 .3 ...... 6179 .6217 .6255 .6293 .6331 .6368 .6406 .6443 .6480 .6517 .4 ...... 6554 .6591 .6628 .6664 .6700 .6736 .6772 .6808 .6844 .6879 .5 ...... 6915 .6950 .6985 .7019 .7054 .7088 .7123 .7157 .7190 .7224 .6 ...... 7257 .7291 .7324 .7357 .7389 .7422 .7454 .7486 .7517 .7549 .7 ...... 7580 .7611 .7642 .7673 .7703 .7734 .7764 .7794 .7823 .7852 .8 ...... 7881 .7910 .7939 .7967 .7995 .8023 .8051 .8078 .8106 .8133 .9 ...... 8159 .8186 .8212 .8238 .8264 .8289 .8315 .8340 .8365 .8389 1.0 ...... 8413 .8438 .8461 .8485 .8508 .8531 .8554 .8577 .8599 .8621 1.1 ..... 8643 .8665 .8686 .8708 .8729 .8749 .8770 .8790 .8810 .8830 1.2 ...... 8849 .8869 .8888 .8907 .8925 .8944 .8962 .8980 .8997 .9015 1.3 ...... 9032 .9049 .9066 .9082 .9099 .9115 .9131 .9147 .9162 .9177 1.4 ...... 9192 .9207 .9222 .9236 .9251 .9265 .9279 .9292 .9306 .9319 1.5 ...... 9332 .9345 .9357 .9370 .9382 .9394 .9406 .9418 .9429 .9441 1.6 ...... 9452 .9463 .9474 .9484 .9495 .9505 .9515 .9525 .9535 .9545 1.7 ...... 9554 .9564 .9573 .9582 .9591 .9599 .9608 .9616 .9625 .9633 1.8 ...... 9641 .9649 .9656 .9664 .9671 .9678 .9686 .9693 .9699 .9706 1.9 ...... 9713 .9719 .9726 .9732 .9738 .9744 .9750 .9756 .9761 .9767 2.0 ...... 9772 .9778 .9783 .9788 .9793 .9798 .9803 .9808 .9812 .9817 2.1 ...... 9821 .9826 .9830 .9834 .9838 .9842 .9846 .9850 .9854 .9857 2.2 ...... 9861 .9864 .9868 .9871 .9875 .9878 .9881 .9884 .9887 .9890 2.3 ...... 9893 .9896 .9898 .9901 .9904 .9906 .9909 .9911 .9913 .9916 2.4 ...... 9918 .9920 .9922 .9925 .9927 .9929 .9931 .9932 .9934 .9936 2.5 ...... 9938 .9940 .9941 .9943 .9945 .9946 .9948 .9949 .9951 .9952 2.6 ...... 9953 .9955 .9956 .9957 .9959 .9960 .9961 .9962 .9963 .9964 2.7 ...... 9965 .9966 .9967 .9968 .9969 .9970 .9971 .9972 .9973 .9974 2.8 ...... 9974 .9975 .9976 .9977 .9977 .9978 .9979 .9979 .9980 .9981 2.9 ...... 9981 .9982 .9982 .9983 .9984 .9984 .9985 .9985 .9986 .9986 3.0 ...... 9987 .9987 .9987 .9988 .9988 .9989 .9989 .9989 .9990 .9990 3.1 ...... 9990 .9991 .9991 .9991 .9991 .9992 .9992 .9992 .9993 .9993 3.2 ...... 9993 .9993 .9994 .9994 .9994 .9994 .9994 .9995 .9995 .9995 3.3 ...... 9995 .9995 .9995 .9996 .9996 .9996 .9996 .9996 .9996 .9997 3.4 ...... 9997 .9997 .9997 .9997 .9997 .9997 .9997 .9997 .9997 .9998