Two quantities x and y are proportional if they are related by:
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Where a is known as the proportionality factor. In this case the quantities related are the length and the weight of a steal beam so the first two question would be:
- What's the length of the beam?
- What's its weight?
Then it is also important to know the proportionality factor so knowing that the length and the weight are proportionally related I would ask:
- What's the proportionality factor?