Cable and Wireless Internet Lite Solver
 Alastair Scott 1998

http://www.unmetered.org.uk/watch/

This Excel 97 spreadsheet allows you to find out after how many hours per month Cable and Wireless Internet *Lite* becomes more expensive than Cable and Wireless Internet for a pattern of Internet use you give it.

To use the spreadsheet:

1. Load it into Excel 97. As the spreadsheet contains macros you may be presented with a dialog box warning you of this; press the Enable Macros button. (The spreadsheet has been virus-scanned using Dr Solomon's Anti-Virus Toolkit 7.87).

2. Make sure you have the Solver Add-In installed: to do this select Tools | Add-Ins... then tick Solver Add-In in the scrolling list and press OK.

3. Under the Online Time subheading, type the percentage of total time spent online (a) during the day and (b) on weekday evenings into the two fields. These fields are highlighted using a slightly lighter yellow than the rest of the spreadsheet.

You don't have to enter percentage of total time spent online at weekends; the spreadsheet calculates that for you using the two values you entered previously.

4. Press the Solve button.

You will see a 'Solver Results' dialog box which may (wrongly) suggest that a feasible solution has not been found; press OK.

5. The result is displayed under the Solution sub-heading.

As a test, daytime 5% weekday 30% and weekend 65% should produce a result of 14 hours 37 minutes.

25 September 1998