Use goal-seek in Excel 2010
Download excel file: http://www.codible.com/pages/46
Description: The goal-seek feature lets you specify a goal- value in a formula, and excel will automatically find the appropriate input value to achieve this goal.
Some good books on Excel and Finance:
Financial Modeling - by Benninga:
http://amzn.to/2tByGQ2
Principles of Finance with Excel - by Benninga:
http://amzn.to/2uaCyo6