posted by Patricia
A boy who weighs 30 kilograms sits on one end of a seesaw. On the other end there is a girl who weighs 20 kilograms. The girl is 1.5 metres from the fulcrum. How far from the fulcrum must be the boy sit in order to balance the seesaw? How far away must the boy sit if the girl is 3 metres from the fulcrum? What conclusion can you make about the seesaw?
the moments about the fulcrum must be equal for balance
moment = mass * distance from fulcrum