Activate and use an add-in

•  Install and activate the Analysis ToolPak and Solver  

Click the File tab.
Click Options, and then click the Add-Ins category.
Near the bottom of the Excel Options dialog box, make sure that Excel Add-ins is selected in the Manage box, and then click Go.
In the Add-Ins dialog box, select the check boxes for Analysis ToolPak and Solver Add-in, and then click OK.
If Excel displays a message that states it can't run this add-in and prompts you to install it, click Yes to install the add-ins.
Note  In this case, because you are installing two add-ins, Excel prompts you to install an add-in twice; once for the Analysis ToolPak and once for Solver.

On the Data tab, note that an Analysis group has been added. This group contains command buttons for Data Analysis and for Solver.

Now you're ready to start using these add-ins.

•  Get started using the Analysis ToolPak  

On a worksheet, click a cell.
On the Data tab, in the Analysis group, click Data Analysis.
In the Data Analysis dialog box, click the tool that you want to use and click OK.

In the dialog box that appears for the tool you chose, enter the parameters and select any options as needed.

•  Get started using Solver  

On a worksheet, enter a formula and then make sure the cell that contains that formula remains selected.
On the Data tab, in the Analysis group, click Solver.

In the Solver Parameters dialog box, choose between Max, Min, and Value Of. If you select Value Of, enter a value in the box.
In the By Changing Variable Cells box, enter a cell or a range for the cells for which you want to solve.
Click Add to add a constraint for a cell, and enter the condition for that cell.
Click Add again to add more cell constraints (you can have multiple constraints for a single cell), and click OK when you are finished. Then click Solve.

The Solver Results dialog box appears, with a success or failure message.