Finding Equations for Multiple Springs in Series

[hallic]

Homework Statement

I have a static spring system with 3 springs holding 2 masses in place I have the spring stiffnesses (K1=1N/m k2=3N/m k3=2N/m) and natural lengths (L1=3m L2=1m L3=2m) and the total length of the compressed springs (x1+x2+x3=4m)

Homework Equations

1/K(total) =1/K1 + 1/K2 + 1/K3

The Attempt at a Solution

I know that I derive simultanious equations and use the iterative or elimination method to solve what the x individual values are but I don't know how to get the equations for 3 springs in series and I can't find a relavent reference in my textbook other than the total of sthe spring constant

 

[Dick]

The forces have to balance at the point where any two springs meet. That's two equations. The sum of the compressions of each spring equals the total compression is the third equation.