# Supply Nodes

## Supply Nodes

Problem 16.5 - PERT/CPM

16.6 a)

b)
Activity ES EF LS LF Slack Critical Path
Start 0 0 0 0 0 Yes
A 0 5 0 5 0 Yes
B 0 1 11 12 11 No
C 1 3 12 14 11 No
D 5 9 7 11 2 No
E 5 11 5 11 0 Yes
F 11 14 11 14 0 Yes
Finish 14 14 14 14 0 Yes

Critical Path: Start  A  E  F  Finish Length = 14 months
c) 6 months

2 a) There are three supply nodes ' the Yen node, the Rupiah node, and the Ringgit node. There is one demand node ' the US\$ node. Below, we draw the network originating from only the Yen supply node to illustrate the overall design of the network. In this network, we exclude both the Rupiah and Ringgit nodes for simplicity.

b) Since all transaction limits are given in the equivalent of \$1000 we define the flow variables as the amount in thousands of dollars that Jake converts from one currency into another one. His total holdings in Yen, Rupiah, and Ringgit are equivalent to \$9.6 million, \$1.68 million, and \$5.6 million, respectively (as calculated in cells I16:K18 in the spreadsheet). So, the supplies at the supply nodes Yen, Rupiah, and Ringgit are -\$9.6 million, -\$1.68 million, and -\$5.6 million, respectively. The demand at the only demand node US\$ equals \$16.88 million (the sum of the outflows from the source nodes). The transaction limits are capacity constraints for all arcs leaving from the nodes Yen, Rupiah, and Ringgit. The unit cost for every arc is given by the transaction cost for the currency conversion.

Jake should convert the equivalent of \$2 million from Yen to each US\$, Can\$, Euro, and Pound. He should convert \$1.6 million from Yen to Peso. Moreover, he should convert the equivalent of \$200,000 from Rupiah to each US\$, Can\$, and Peso, \$1 million from Rupiah to Euro, and \$80,000 from Rupiah to Pound. Furthermore, Jake should convert the equivalent of \$1.1 million from Ringgit to US\$, \$2.5 million from Ringgit to Euro, and \$1 million from Ringgit to each Pound and Peso. Finally, he...