In this figure you can see that a long lever, fixed at the left end, has weight applied to it very close to the fixed end. At the right end of the lever the weight is significantly reduced by a ratio determined by the relative difference between the length from the left end to the weight and the distance from the left end to the right end. As you can see in this diagram, the ratio is 1:12. So if a 120pound person stands on the scale, only 10 pounds is felt at the right hand end of the scale. The following three figures show the arrangement of the levers in this scale:

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