Answer:
a. Develop a network representation of the problem:
b.
c.
180 100 160 Avery 115 \100 120 135 Baker 160 115 Van 100 135/ 150 140 Campbell 140 130
LPP Max noor11 = 123x12 + 1513 : 1eos 14 + 12021 + 1352 + 123 + 120x24 - 15331 : 150x32 + 140x3 + 13034 11 +[ 12 +[ 13 +14 21 + 122 | 23 | 24 st. + 32 + x33 + x 34 11 | x31 + x 31 + | 21 | + x22 12 12 + 32 در 13 | + x33 + | 23 x 14 |+ | 24 | + x 34 xij >= 0 for all i,j
|_ A B C D E F G H Client A B C D 125 2 Consultant 3 Avery 100 Baker 120 5 Campbell 155 135 150 115 115 140 100 120 130 D =SUM(B10:E10) <= 160 =SUM(B11:E11) <= 160 =SUM(B12:E12) <= 140 Client 9 Consultant A B C 10 Avery 11 Baker 12 Campbell 13 =SUM(B10:B12) I=SUM(C10:C12) I=SUM(D10:012) 14 75 100 16 17 Total Rate =SUMPRODUCT(B3:E5,B10:E12) =SUM(E10:E12) 180
Solver Parameters Set Objective: $D$17 To: O Max O Min O Value Of: By Changing Variable Cells: $B$10:$E$12 Subject to the Constraints: $B$13:$E$13 = $B$15:$E$15 $F$10:$F$12 <= $H$10:$H$12 Add Change Delete Reset All Load/Save v Make Unconstrained variables Non-Negative Select a Solving Method: Simplex LP Options Solving Method Select the GRG Nonlinear engine for Solver Problems that are smooth nonlinear. Select the LP Simplex engine for linear Solver Problems, and select the Evolutionary engine for Solver problems that are non-smooth. Help Solve Close
A B E F. G H 1 2 3 4 5 Consultant Avery Baker Campbell А. 100 120 C D Client LBC 125 115 135 115 150 140 100 120 130 155 Client A 0 / <= L 8 9 Consultant 10 Avery 11 Baker 12 Campbell 13 в 40 35 0 с 100 0 0 100 D 0 85 O 85 140 160 40 160 160 140 140 140 180 15 180 75 1 100 85 16 17 Total Rate 57925
Hours Assigned Billing O 5000 11500 0 Avery-Client A Avery-Client B Avery-Client C Avery-Client D Baker-Client A Baker-Client B Baker-Client C Baker-Client D Campbell-Client A Campbell-Client B Campbell-Client C Campbell-Client D Total Billing 40 100 0 40 35 0 4800 4725 85 140 10200 21700 O 0 0 O 57925
If Campbell cannot work any more x31, x32, x33, 234 = 0 Avery and Baker can handle up to two clients at a time. HEnce, aij, a binary variable, represent the decision to which clients are the consultants handling, with aij = 1 if the consultant i is handling client j and aij = 0 if consultant i is not handling the clinetj. Added constraint: all + al2 + al3+ al4 = 2 a21 + a22 + a23+ a24 = 2 Avery and Baker can work with all clients, have now double the amount of previous time to work, hence, the supply constraints change to: Supply constraints: xll* all + x12* al2 +xl3* al3 +x14* al4 <= 320 ( Avery) X21* a21 +*22* a22 +x23* a23 +x24* a24 <= 320 ( Baker) Demand Constraints: xll* all + x21* a21 = 180 (Client a) x12* al2 + x22* a22 = 75 (Client b) x13* al3+x23* a23 = 100 (Client c) x14* al4 + x24* a24 = 85 (Client d)
ДА E G H Client ATBT 2 Consultant Avery 4 Baker 3 Avery 100 120 100 - 125 115 5 IB = =SUM(B8:E8) =SUM(B9:59) 10 Client 7 Consultant Avery 9 Baker Avery Baker 12 13 Avery =B8*B10 =C8*C10 =D8*D10 14 Baker =B9*B11 =C9*C11 =D9*D11 =SUM(B13:B14) =SUM(C13:C14) =SUM(D13:014) 11 =E8*E10 =E9*E11 =SUM(E13:E14) =SUM(B13:E13) <= =160*2 =SUM(B14:E14) <==160*2 180 75 100 85 Total Rate =SUMPRODUCT(B3:E4,B13:E14)
X Solver Parameters Set Objective: $D$19 To: O Max O Min O Value of: By Changing Variable Cells: $B$8:$E$9,$B$10:$E$11 Add Subject to the Constraints: $B$8:$E$9 = binary $F$13:$F$14 <= $H$ 13:$H$14 $B$15:$E$15 = $B$17:$E$17 $F$8:$F$9 = $H$8:$H$9 Change Delete Reset All Load/Save v Make Unconstrained variables Non-Negative Select a Solving Method: GRG Nonlinear Options Solving Method Select the GRG Nonlinear engine for Solver Problems that are smooth nonlinear. Select the LP Simplex engine for linear Solver Problems, and select the Evolutionary engine for Solver problems that are non-smooth. Help Solve Close
2 3 4 Consultant Avery Baker A 100 120 DE F Client D 115 100 115 120 125 135 Client A 0 0 7 8 9 10 11 12 Consultant Avery Baker Avery Baker 180 7620 100 Avery Baker 0 180 180 175 265 320 320 O <= 100 180 100 | Total Rate 52675
Total billings have reduced. An Revised schedule: Client BC 75 100 0 0 Avery Baker 180 85 Hours Assigned Billing 9375 11500 100 0 Avery-Client A Avery-Client B Avery-Client C Avery-Client D Baker-Client A Baker-Client B Baker-Client C Baker-Client D Total Billing 180 21600 O 10200 52675