**LBtaekwondo**On my form, folks select a week or weeks to enroll their kids for camp. They need to be charged a deposit of $50 per child/ per week.

My payment field asks them how many children they are registering and charges $50 for each, but I need that amount to then be multiplied by the number of weeks they have selected from the check boxes. How can I make this work?

- JotForm Support
**TitusN**Hello,

You can achieve this by using the calculation widget. You can assign values to each of the week selections, then the calculation widget can capture those values when selected, and multiply the total with the number of children from a drop down field. The total can then be passed to Paypal from the calculated total.

Here are the steps that you can use to achieve that.

1. Assign a value to

**each**of the week check-boxes - I'm assuming each selected option amounts to one week. The values will be used with the calculation widget to give the total selected weeks:2. Add a dropdown field for the number of children.

3. Add a calculation field/widget that will calculate the total amount:

4. On your Paypal field, configure it to use the calculated total as shown in this guide.

You can hide the calculation field so that your users don't see it as shown below:

Let us know if you hit any bumps.

**LBtaekwondo**Thank you, kind stranger!!

- JotForm Support
**ashwin_d**Hello LBtaekwondo,

On behalf of my colleague, you are welcome.

Do get back to us if you have any questions.

Thank you!