Equilibrium problem...

A woman is using a lever to lift a heavy object. The lever consists of a uniform plank of wood pivoted.(There is 2.2m between the woman and the pivot.) The plank is 3.0m long and weighs 200N. (0.8m between the pivot and the heavy object the other side). The heavy object weighs 1200N

Calculate the downward force F she needs to apply to keep the plank balanced.

Any ideas how to do this???
Thanks :)

set this up as a torque problem
where CCW torque = CW torque
I put the woman at the left end of the lever 2.2m from pivot
the weight of the lever is 200 N which acts downward at the midpoint of the uniform lever
this point is 0.7 m from the pivot on the same side as the woman
the load (object) is 0.8 m to the right of the pivot
so
Fw(2.2) + 200(0.7) = 1200(0.8)
solve for the force exerted by the woman (Fw)

I get about 373 N

Sketch the situation - even if it is shown as a diagram - re-draw it UR self so that U can see that:
1)
The heavy object applies its TORQUE aka MOMENT CCW about the pivot.
The numeric value of this torque = (1200)(0.8) = 960 m-N {acts CCW}

2)
The plank the woman uses also applies a TORQUE/MOMENT but it acts at the CM of the plank which is 1.5 m from its ends.
So plank's Torque value = (200)(1.5) = 300 m-N CW

3)
The downward force{F} that woman must generate a CW torque equal to:
960 {CCW} - 300 {CW} = 660 m-N CW
the above equation simply states that the Torque/Moment applied by the weight on the one side of the pivot must equal the Torque/Moment applied by all the other forces
{F + plank's wt} on the other side of the pivot. ie Σ CCW Torque = Σ CW Torque.

Divide the required Torque applied by woman = 600 m-N by the distance it's applied from pivot to find the value of F.