Solve Torque Problem: 1.42M at 41.6 cm?

[NasuSama]

Homework Statement

Suppose the ruler in procedure 2 is asymetrical, and it is balanced at the 40.9 cm mark (at the center of mass). Now, mass M is hung on the ruler at the 100 cm mark. Where must you hang mass 1.42M so the system remains in equilibrium?
At the ... cm mark

Homework Equations

Torque equations...

The Attempt at a Solution

I think it goes this way...

1.42Mg(x) = Mg(100 - 40.9) where x is the distance from the 0 cm mark

Then, I get x ≈ 41.6 cm, but it's marked incorrect.

 

[NasuSama]

Wait. It's..

1.42Mg(40.9 - x) = Mg(100 - 40.9)

Then, I obtain negative value, which is around...

x ≈ -0.720

 

[NasuSama]

What is a difference between x = 41.6 cm and the negative value -0.72 cm? There should be a difference between them.