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WHY DOES USA USE A DIFFERENT METRIC SYSTEM?

How many times have we listened to words such as "inches" or "miles", which we are not accustomed to use. Where are these measurement units used? and, why are there different measurement systems? But lets go one step at a time. 

The United States is one of the few countries in the world that does not use the metric system, because it uses the so-called Anglo-Saxon system of units where the kilogram, liter and kilometer are replaced by other measures that the less we understand. There are different ways of measuring weight, volume, distance and temperature, among other things, and they tend to be grouped within different systems. In almost all the world we use the metric system, but the United States is one of the few countries that does not use it. And this has a historical reason.

[Wood engraving, which is from 1800, that shows 
 the new  decimals units that were  legal 
in France since  November 4 1800.]


The metric system was born in the French Revolution as a way to standardize the patterns in which the units were measured and it was spread to almost all the rest of Europe and also, to the countries that were colonies of that European countries.

That attempt to unify the units of measures never progressed in England and great part of the Anglo-Saxon countries, those that they were already independent, did not want to adapt, being the United States one of them.

The so-called Anglo-Saxon system of units is used in the United States, which varies slightly from the English imperial system. The main units of measurement of it are: inches, feet, yards, miles, ounces, gallons and, in the case of temperature, the Fahrenheit degrees. In order to make clearer the conversions between units of measurements, I would like to share following tables:
















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