Let M be load.
∴ Load arm = 90 – 60 = 30 cm
Since wt. of scale will act at centre of gravity of scale which is the midpoint of the scale.
∴ Effort arm = 60 – 50 = 10 cm
Let wt. of scale be W
By principal of moments L × dL = E × dE
M × 30 = W × 10 W = 3M
∴ Since weight of scale is three times that of M.
∴ Weight of scale is greater than weight of M.