How make formula calculation

I see this is a nice extension but I don't get it how to make calculations.

I have a form where people can choose from a list a few options.
Option 1 = 20 euro
Option 2 = 30 euro
Option 3 = 40 euro, etc.

In the next field they have to choose how many items from a list, 1, 2, 3, 4 etc.

I don't get how I can make the calculation. Option x how many = total. F.e. Option 2 x 3 = 90 euro.

Can anybody help cause I can't find example forms.

As replied via support, it would require a clever setup and hard to explain. So better, send us super admin account of your site via support ticket so that our support staff can help

Tuan

For people who want this also it was pretty simple. I made the mistake that I thought I had to choose 'depend on field'. But that was wrong.

The only thing you have to add is the formula in the last field.

[NUMBER_PARTICIPANTS]*[EVENT]

So in my case you choose an EVENT and you add a price to the events. In the second field you choose the NUMBER_PARTICIPANTS and you set the formula. Works flawlessly. Tuan gives great support and answered all my questions very fast and well.

Very happy with this awesome support. Very much appreciated. In one day I was able to set this up the right way with his help and the form is working live now, including the added extension for Mollie (payments) that I also bought here.

Just want to add more information to the needed setup:

1. Just one of the two fields need to be Fee Field. The one with Formula setup needs to be Fee Field, for the other field, Fee Field need to be set to No

2. For the other field (which fee field set to No), you will still have to setup Fee Values (allow it is not fee field). The Fee Value for each option which you setup will be used in Fee Formula to calculate fee which users have to pay on the form

Tuan