**jennymccann**Hi,

I am attempting to create a contract for my wedding photography business. I have 3 packages clients can choose from and I currently have those set up with radio buttons. My question is, since I also require a down payment to secure a date can I use the calculation tool to subtract that $ amt from the final payment. - Depending on which radio button they chose, the final payment would change. Can I do that?

Thanks for your help.

Jenny McCann

- JotForm Support
**Welvin**Hi Jenny,

You should be able to do that in our calculation widget. The formula should be:

**Total - Downpayment**then the result is the**Balance**.But for this to work, I would advise using the

**Textbox**field for the**Downpayment**field so you can input values. Calculation widget is read-only.Here's an example form: http://www.jotformpro.com/form/40894331220952

Sounds good? Let us know if you have any further questions.

Thanks

- JotForm Support
**Welvin**By the way, here's the calculation guide: How to perform calculation in the form?.

Thanks

**jennymccann**Awesome!!! Thank you so much for your help. I really really appreciate it.

Is there also a way for the date tool to subtract 30 days? I will have clients enter their wedding date and I require full payment 30 days BEFORE the wedding date. So I was wondering if there was a way to have it automatically populate that date.

- JotForm Support
**EltonCris**@jennymccann

That's possible with datestring math function.

Example:

Demo: http://form.jotformpro.com/form/40881718184966?

If this isn't what you mean, let us know here.

Thanks!

**jennymccann**Thank you again for your fast responses!!