Contents

- 1 How many decision variables are allowed in Excel Solver?
- 2 What are the three required parameters of a Solver model and what do they represent?
- 3 What is Solver used for?
- 4 How many constraints can Solver have?
- 5 Why can’t solver find a feasible solution?
- 6 What is a decision variable in linear programming?
- 7 What is the best explanation of decision variables?
- 8 Can solver change multiple cells?
- 9 When would you use simplex LP?
- 10 What are the different conditions we can apply in Solver constraints?
- 11 Under which tab we can see the Solver tool?
- 12 Does Solver work with if statements?
- 13 Why does my Solver take so long?
- 14 What are constraints in Excel Solver?

## How many decision variables are allowed in Excel Solver?

The standard Microsoft Excel Solver has a limit of 200 decision variables, for both linear and nonlinear problems.

## What are the three required parameters of a Solver model and what do they represent?

There are three required parameters when running a Solver model: the objective cell that you want to maximize, minimize, or set to a specific value; the variable cell(s) that Solver uses to produce the desired results in the objective cell; and the constraint(s) that limit how to solve the problem.

## What is Solver used for?

Solver is a Microsoft Excel add-in program you can use for what-if analysis. Use Solver to find an optimal (maximum or minimum) value for a formula in one cell — called the objective cell — subject to constraints, or limits, on the values of other formula cells on a worksheet.

## How many constraints can Solver have?

You can add a maximum of 100 constraints.

## Why can’t solver find a feasible solution?

This message appears when Solver could not find any combination of values for the decision variables that allows all of the constraints to be satisfied simultaneously. Most often this is due to choosing the wrong relation (e.g. <= instead of >=) on an otherwise appropriate constraint.

## What is a decision variable in linear programming?

Decision Variables: The decision variables are the variables that will decide my output. They represent my ultimate solution. To solve any problem, we first need to identify the decision variables. For the above example, the total number of units for A and B denoted by X & Y respectively are my decision variables.

## What is the best explanation of decision variables?

A decision variable is a quantity that the decision-maker controls. For example, in an optimization model for labor scheduling, the number of nurses to employ during the morning shift in an emergency room may be a decision variable. The OptQuest Engine manipulates decision variables in search of their optimal values.

## Can solver change multiple cells?

It’s important to remember that you can select multiple cells for Cell Reference. If you want six variables to have values over 10, for example, you can select them all and tell Solver that they must be greater than or equal to 11.

## When would you use simplex LP?

Simplex LP – This is used to solve linear problems. Evolutionary – This is used to solve more complex and non-smooth non-linear problems. It looks for a global optimal solution, which makes it take longer to run compared to GRG Nonlinear.

## What are the different conditions we can apply in Solver constraints?

Constraints are logical conditions that a solution to an optimization problem must satisfy. They reflect real-world limits on production capacity, market demand, available funds, and so on. To define a constraint, you first compute the value of interest using the decision variables.

## Under which tab we can see the Solver tool?

The solver tool can be activated in excel from Excel Options under the tab Add-Ins. We will be able to see this in the Data tab under the analysis section as Solver. In Solver, we just need to add the cell formula or problem, then select the cells that are affecting it.

## Does Solver work with if statements?

You can use discontinuous functions such as IF and CHOOSE in calculations on the worksheet which are not dependent on the decision variables, and are therefore constant in the optimization problem. But any discontinuous functions that do depend on the variables will likely cause problems for the Solver.

## Why does my Solver take so long?

If you use a large, arbitrary bound (upper or lower), a solver can take excessive time, or even fail to converge. However, if you set Inf or -Inf as the bound, the solver can take less time, and might converge better.

## What are constraints in Excel Solver?

Creating constraints lets you restrict the changes that Excel can make to your cell values. For example you may always want a value to be between 10 and 30 or to not be less than 200. You can add a constraint by clicking on the Add button.