Multiple draggable movieclip within the x and y axis of another movieclip

I have this four draggable movieclips. I have able to drag the green bar within the gray bar and the dynamic percentage text increase/decrease accordingly.

The program should make the second draggable determine the percentage of the first (100 - current value) and make it the basis for the other 3 draggable.

Example:

if the 1st draggable will be 75%. the other 25% will be divided by the other 3 draggables.

The 3rd draggable determine the 2nd percentage (100 - current value) and make it the basis for the other 2 draggable and so on.

When I drag the 1st draggable the other 3 is drag & animated accordingly but I cannot drag the 2nd, 3rd and 4th draggable.