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How To Measure Distances on a Map

By Matt Rosenberg, About.com

Maps aren't just useful for directions, they can also help you determine the distance between two (or more) places.
Difficulty: Average
Time Required: 5 minutes

Here's How:

  1. Find the scale for the map you're going to use - it might be a ruler-looking bar scale or a written scale, in words or numbers.
  2. Use a ruler to measure the distance between the two places. If the line is quite cureved, use a string to determine the distance and then measure the string.
  3. If the scale is a representative fraction (and looks like 1/100,000 or 1:100,000), multiply the distance of the ruler by the denominator, giving distance in the ruler units.
  4. If the scale is a word statement (i.e. "One centimeter equals one kilometer") then determine the distance.
  5. For a graphic scale, you'll need to measure the graphic and divide the scale into the measured units on the ruler.
  6. Convert your units of measurement into the most convenient units for you (i.e. convert 63,360 inches to one mile)

Tips:

  1. Watch out for maps that have been reproduced and have had their scale changed. A graphic scale will change with the reduction or enlargement but the other scales become wrong.

What You Need:

  • Ruler
  • String
  • Map
  • Calculator

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