We have a form for membership.
Classes are taught twice a week but membership give the user an option to sign up for one day or two days and to determine if there are more than one persons signing up for the class.
In the custom fields, we have a user input how many members they want to sign up for a single class during the week.
We have another custom field that lets users add an extra day and the amount of users.
Adding an extra day is at a lower cost per class.
Is it possible to hide the "extra day" field until someone adds a number of members in the first field?