Answer:
adjust the weights until balance is achieved
Step-by-step explanation:
Start with all of the beam weights in their 0 position.
Move the heaviest weight to successive positions farther from 0 until the beam falls. Move it back one.
Move the next-heaviest weight to successive positions farther from 0 until the beam falls. Move it back one.
Move the lightest weight along the scale away from 0 until the beam is centered in the space.
The weight of the object in the tray is the sum of the marks on the scales associated with the three weights.
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It helps if the device is "calibrated" before you add anything to the pan. When the pan is empty and all beam weights are in their 0 position, the beam should be centered in its space. If not, adjust the zeroing device until it is.
The attached picture shows a typical laboratory triple-beam balance. It is capable of measuring weights up to 610 grams with a resolution of 0.1 grams or better.
