I'm making an application that need to use a function like 'goal seek' in Excel. Here's the problem example:

Price: 100.000
Down Payment: 20% -> 20.000
Payment per month: 8.000 (assume a 10 month period)
Total Down Payment: 28.000 (20% of 100.000 + 8.000 first payment)

Now I want the Total Down Payment to be 30.000, so I need to change the Down Payment of 20% to another value. In Excel, I can use the Goal Seek Function to do this very easily, and the Down Payment results in 22,2222%.

How do I do it in VB?

Thanks.