**MCAMF**How can I make sure the number of people being registered matches the number being paid for? I have an input table to capture the number of people in the party and all over age 2 need a ticket. I'd like to generate an error message if they try to pay for a different (lesser) number than is required.

- JotForm Support
**liyam**The solution I could think of is by setting your products outside the payment field such as that "Number in your party" field on the screenshot. Then add a form calculation widget on your form where the quantity or number entered shall compute to the amount per head. Then on your payment field, the amount shall be sourced from the result of the calculation widget.

Here is a sample form I cloned from yours and which I made modifications: https://form.jotformpro.com/72191361748965

Feel free to test out the form and even clone it if you like.

Here is a user guide on how to use the form calculation widget on your form to collect payments: https://www.jotform.com/help/275-How-to-Pass-a-Calculation-to-a-Payment-Field

*Note: The product item will not appear on your payment gateway. So you will need your JotForm submissions as reference.*Feel free to get back to us if you have questions.

**MCAMF**Perfect! That is exactly what I was trying to do. How do I clone it? I only know how to clone my own forms from within my account.

...**MCAMF**Never mind, I found the import function. Thanks again!

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