Cook don't implements such formules.
Open your controller related to this table, and add in the save() function, all theses calculs.
Something like this:
$myTotal = 0;
if (isset($data['senior_entry']) && $data['senior_entry'])
$myTotal += 10;
$data['total'] = $myTotal;
Before the save() model call.
Be careful with checkboxes :
If the controller save function is raised by another call without the senior_data value, it must not detect as value = 0.
So, you must check if $data is set.
But if you use a checkbox in the form, it seems not initialize the data if not checked. Personally, I use an hidden field with the same name, and value = 0, Just before the checkbox input.
I don't know if it is the best method.
Hope you understood.
the best is to