algebra question

Question

A child with a mass of 25 kg is sitting 2 m from the fulcrum of a seesaw. How far from the fulcrum should a 100 kg adult sit in order to balance the seesaw? (You do not need to answer in a complete sentence.)

Answer 1

Force 1 x Distance 1 = Force 2 x Distance 2

so

25kg x 2m = 100kg x ?m

25 x 2 = 50

50 = 100x?

divide by 100

One-half meter is the appropriate distance.