Drop down box controlled by input of another

I'm not sure of the exact term, but what I'm looking for is one combo box that controls another. Such as the example below:

(Drop down box 1) Booth Size:
(option 1) 10x10
(option 2) 10x20

(Drop down box 2) Number of booth staff:
the result should be..

if 10x10 is selected in Drop down box 1, result = "2 staff"
if 10x20 is selected in drop down box 1, result = "3 staff"

Thanks!

Hi acaddy,

I'm not sure what to call them either - but I usually use 'double-drop-down'. You'll find several threads here on different flavours. It sounds as though your application would work with a little JavaScript.

Bob