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Question
A boy of mass 30 kg is fitting at a distance of 2 m from the middle of a see-saw. Where should a boy of mass 40 kg sit so as to balance the see-saw?
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Solution
By the principle of moments 30 × 2 = x × 40
∴ Other boys should sit at a distance
x =`(30xx2)/40`
= 1.5 m
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