Office challenge: Why aren't my formulas calculating correctly?

This week, test your Excel skills against a workbook that suddenly stops calculating correctly.

You open a workbook to make a few enhancements. You enter a new formula and then copy it, but instead of displaying the expected results, the copied formulas display the result of the first formula.

Each formula in row 10 displays $7,806! What's going on?

By Susan Harkins

Susan Sales Harkins is an IT consultant, specializing in desktop solutions. Previously, she was editor in chief for The Cobb Group, the world's largest publisher of technical journals.