IMPORTANT NOTE:

You can do this by putting a custom action on the element. For example, if you are using a select-list to show the number of travelers -- say from 1 to 6 -- your list would look like this:

0;1;1
0;2;2
0;3;3
0;4;4
0;5;5
0;6;6

For the purpose of this example, let's name the element NumberOfTravelers.

Then go to the Advanced tab of the select-list.

Type: CUSTOM
Action: CHANGE (third checkbox from the left)

Click on CREATE CODE FRAMEWORK. A screen will popup that says:

Create code framework for action now?
(Existing code will be appended)

Click on OK. In the text area, you will see something like this:

function ff_NumberOfTravelers_action(element, action)
{
    switch (action) {
        case 'change':
            break;
        default:;
    } // switch
} // ff_NumberOfTravelers_action

Change it to:

function ff_NumberOfTravelers_action(element, action)
{
    switch (action) {
        case 'change':
if( element.value == '1' ){
  ff_switchpage(7);
} else if( element.value == '2' ){
  ff_switchpage(2);
} else if( element.value == '3' ){
  ff_switchpage(3);
} else if( element.value == '4' ){
  ff_switchpage(4);
} else if( element.value == '5' ){
  ff_switchpage(5);
} else if( element.value == '6' ){
  ff_switchpage(6);
}
            break;
        default:;
    } // switch
} // ff_NumberOfTravelers_action

IMPORTANT: If your element is named something OTHER than NumberOfTravelers, then you need to change the function to match the name. For example, if your element is named Travelers, then the function line would change to:

function ff_Travelers_action(element, action)