​​The Unit Rate as the Scale Factor

What is SCALE FACTOR?

• ​A scale factor in math is the ratio between corresponding measurements of an object and a representation of that object.

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• The scale factor can be calculated from the ratio of any length in the scale drawing to its corresponding length in the actual picture. The scale factor corresponds to the unit rate and the constant of proportionality. Scaling by factors greater than 1 enlarges the segment, and scaling by factors less than 1 reduces the segment.

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​TYPES OF SCALE DRAWINGS

• If the scale drawing is LARGER than the original, then it is an enlargement.

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• If the scale drawing is SMALLER than the original, then it is a reduction.

​Steps to check for proportionality for scale drawing and original object or picture

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1. ​Create a table and record the lengths of the scale drawing on the table.

2. ​Record the corresponding lengths of the actual/original object or picture on the table.

3. ​Check for constant of proportionality by dividing scale drawing lengths by the original lengths.