posted by joey .
an adult and a s,all child get on a seesaw that has a movable fulcrum. when the fulcrum is in the middle, the child can't tift the adult. How should the fulcrum be moved so the two can seewaw
I gave you the answer. I assume, now, that you don't have numbers to plug into the equation. But you should figure out from the equation, that qualitatively, the fulcrum must be moved toward the adult.
Adult goes down. Child goes up.
So you move the fulcrum closer to the adult.
Now they can see-saw.