David and his father sat at the end of a see-saw 2 m from the pivot. where should David's mother sit in order to balance the see-saw

Answer 1

Hard to say with that little information about masses.

Answer 2

Force multiply by distance(1)+ force multiply by distance(2)= force multiply by distance(3)
400N multiply by 2m + 600d =700N multiply by 2m
800+600d=1400
600d=1400-800
600d=600
d=1m

Answer 3

400N multiply by 2m + 600d =700N multiply by 2m
800+600d=1400
600d=1400-800
600d=600
d=1m

Answer 4

Midlle of the pivot

Answer 5

Moment1=Moment2
Force1xDistance1=Force2xDistance2
(400Nx2m)+(600NxD)= 700Nx2m
800Nm+(600NxD)= 1400Nm
600NxD= 1400Nm-800Nm
600NxD= 600Nm
D= 600
➖➖➖ <-(600N upon 600Nm)
600
D= 1m ✔