CHAPTER 4 LINEAR PROGRAMMING;SIMPLEX METHOD

(USING EXCEL)

SOLVER

Excel includes a tool called solver that uses techniques from the operations research to find optimal solutions for all kind of decision problems.

Load the Solver Add-in

To load the solver add-in, execute the following steps.

1. On the green File tab, click Options.

2. Under Add-ins, select Solver Add-in and click on the Go button.

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3. Check Solver Add-in and click OK.

4. You can find the Solver on the Data tab.

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Solving a Maximum Problem Using Excel

Mikes’s Famous Toy Trucks specializing in making four kinds of toy trucks; a delivery truck ,

a dump truck , a garbage truck and a gasoline truck. Three machines –a metal casting machine,

a paint spray machine, and a packaging machine are used in the production of these trucks .The

maximum time available per week for each machine is given as : metal casting ,4000 hours ,

paint spray , 1800 hours and packaging ,1000 hours. The time, in hours ,each machine works to

make each type of truck and the profit for each truck are given .

How much of each type of trucks be produced to maximize the profit ?

SOLUTION:

Maximize P=0.5 x1+x 2 +1 .5 x3+2 x4

Subject to the constraints

2 x1+ 2 .5 x 2 + 2x3+2x4≤4000x1+ 1 .5 x 2 + x3+2x4≤18000 . 5 x1+ 0 .5 x 2+ x3+x4≤1000x 1 ≥0 , x2≥0 , x3≥0 , x4≥0

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Step 1

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Solving a Minimum Problem Using Excel

EXAMPLE 5

Minimize C=6 x1+8 x 2 +x3

Subject to the constraints

3 x1+5 x 2 +3 x3≥20x1+3 x 2 +2 x3≥96 x1+2 x 2 +5 x3≥30x 1 ≥0 , x2≥0 , x3≥0

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