There are a number of reasons to figure the midpoint between two locations for a specific set of directions. When arranging custody pickup and dropoff points, going on vacation or traveling for business, the midpoint of a journey can offer a good stopping point for the night or a valuable meeting location. The midpoint is simply the average between two points and is relatively easy to compute mathematically. Perhaps more valuable is the ability to convert that mathematical number into location information along your planned route.
Things You'll Need
 Directions
 Map
 Calculator

Calculate the total distance between your starting and ending location. This can be done by adding together the distance traveled on the roads between your point of origination and your destination. It can also be done by putting your starting and ending address into a route finder like Mapquest, which gives you the total distance for the directions you are following. For example, the total distance between Jefferson City, Missouri, and St. Louis is 126.16 miles if traveling predominately on U.S. Route 50.

Divide the total distance by 2 to calculate the midpoint in the directions. For example 126.16 miles / 2 = 63.8 miles. So, the midpoint between Jefferson City and St. Louis is 63.8 miles down along U.S. Route 50 from either city.

Find the town on the map nearest the midpoint. Express the midpoint in miles from the city nearest the midpoint. For example, the village of Leslie is nearest the midpoint location between Jefferson City and St. Louis. So you would say the midpoint is approximately 2 miles from Leslie.
Tips & Warnings
 Websites such as Geo Midpoint or Rendeznew will find the midpoint between any two addresses for you. They will also allow you to perform a search to find shopping locations, restaurants, hotels and other amenities nearest your midpoint.
References
 "Shortcut Algebra 1"; Andrew Marx; 2007
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