U.S. System vs. Metric System: Length Conversions

• 1 inch = 2.54 centimeters
  1 foot = 0.3048 meters
  1 yard = 0.91 meters
  1 mile = 1.61 kilometers
  
  

U.S. Customary vs. Metric System: Weight Conversions

• 1 ounce = 28.35 grams
  1 pound = 0.45 kilograms
  1 US ton = 0.91 metric tons
  
  

U.S. Customary vs. Metric System: Temperature Conversions

• When converting temperatures, remember these formulas:
  
  C = (F - 32) / 1.8
  F = (C x 1.8) + 32
  
  Where:
  C = Celsius
  F = Fahrenheit
  
  

U.S. Customary vs. Metric System: Area and Volume Conversions

• Area Conversions:
  1 acre = 0.40 hectares
  1 square inch = 6.45 square centimeters
  1 square foot = 0.09 square meters
  1 square yard = 0.84 square meters
  1 square mile = 2.60 square kilometers
  
  Volume Conversions:
  1 teaspoon = 4.93 milliliters
  1 tablespoon = 14.79 milliliters
  1 fluid ounce = 29.57 milliliters
  1 pint = 0.47 liters
  1 quart = 0.95 liters
  1 gallon = 3.79 liters
  
  

Why the Metric System Is Easier to Use

• Unlike the U.S. Customary system, conversions between metric system units are easy and precise because they are based on the decimal system. For example, if you want to convert kilometers to meters, you simply multiply the kilometers by 1,000. However, if you want to convert miles to feet, you have to multiply the number of miles by 5,280. This is clearly a more difficult calculation.
  
  

Why Haven't We Converted to Metric?

• Many people wonder why we are the only Western country still using such a complicated system for measurement. The main reason is because our system has been in place for such a long time that people have gotten used to it. Back in the 1970s, there was a movement to change to the metric system. For example, cereal boxes included their metric weights. The government even had a plan to officially make the switch to metric. However, the plan was never carried out, mainly due to concerns about people resisting the big change. The U.S. customary system may be here to stay.