Question

Two boys each of mass 10kg sit at a distance 1.5metres from a pivot of a seasaw. If another boy of mass 30kg sit at the distance 1.0metres from the pivot, would the seasaw balance horizontally?

Answer 1

30(1)=2*10*1.5 ???
30=30
yes.

Answer 2

No, because the seesaw was already balanced. So, when the 3rd boy climbed on, it became unbalanced.
Balanced: F1*d1 = F2*d2.
;

Answer 3

I assumed the 2 boys were on opposite sides of the pivot; because if they were on the same side, they occupied the same space at the same time which is impossible.