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Customary units - Definition with Examples
Customary system
The customary system of measurement is defined as a set of weights and measures used for measuring length, weight, capacity, and temperature. Based on the English system of measurement, it is also known as the U.S. Customary System.
The customary units to measure length and distances in the customary system are inches, feet, yards, and miles.
| Customary Units for Measuring Length |
|||
| Inches |
Feet |
Yards |
Miles |
We can use the given chart for conversion of one customary unit of length to another.
Example: Convert 5 foot to inches.
1 foot = 12 inches
5 foot = 12 × 5 = 60 inches
The table given below shows the relation between customary units and standard metric units.
| Customary Unit |
Customary Equivalent |
Standard Metric Equivalent |
| 1 inch |
-- |
2.54 centimeters |
| 1 foot |
12 inches |
0.3048 meters |
| 1 yard |
3 feet |
0.9144 meters |
| 1 mile |
1760 yards |
1.609 344 kilometers |
The U.S. customary units for measuring weight are ounces, pounds, and tons.
| Customary Units for Measuring Weight |
||
| Ounces |
Pound |
Ton |
We can convert the customary unit of weight by using the giving relations.
Example: How many ounces are there in 1 ton?
1 ton = 2000 pounds
1 pound = 16 ounces
So, 2000 pounds = 2000 × 16 = 32000 ounces
| Customary Unit |
Customary Equivalent |
Standard Metric Equivalent |
| 1 ounce |
-- |
28.349523125 grams |
| 1 pound |
16 ounces |
453.59237 grams |
| 1 ton |
2000 pounds |
907.18474 kilograms |
The U.S. customary capacity or volume measurement units are ounces, cups, pints, quarts, and gallons.
| Customary Units for Measuring Capacity (Volume) |
||||
| Fluid Ounce | Cup | Pint | Quart | Gallon |
Example: Convert 3 quarts to cups.
1 quart = 2 pints
3 quarts = 6 pints
1 pint = 2 cups
6 pints = 6 × 2 = 12 cups
| Customary Unit |
Customary Equivalent |
Standard Metric Equivalent |
| 1 fluid ounce |
2 tablespoons |
29.5735295625 milliliters |
| 1 cup |
8 fluid ounces |
236.5882365 milliliters |
| 1 pint |
2 cups |
473.176473 milliliters |
| 1 quart |
2 pints |
0.946352946 liters |
| 1 gallon |
4 quarts |
3.785411784 liters |
The U.S. customary measurement unit for temperature is °Fahrenheit.
1 °C = 33.8 °F
| Fun Facts
|
What are customary units of length?
In the US customary system, inch, foot, yard, and mile are used for measuring length. 1 foot = 12 inches, 1 yard = 3 feet, and 1 mile = 1,760 yards.
How many countries use customary units?
There are three countries in the world that use customary units – the United States, Myanmar, and Liberia. The majority of countries use metric units and a few countries use a hybrid system.
What are some advantages of using metric units instead of customary units?
In the metric system, units have the same root word & only the prefix changes (e.g., millimeter, centimeter, decimeter, etc.), so they are easier to learn. In the US customary system, units do not sound alike (e.g., inch, foot, yard).
Are imperial and customary systems the same?
Imperial and customary systems are not exactly the same. Units such as cubic inches, cubic feet, etc. are the same in both systems, however, units like bushels, gallons, etc. are different in the two systems. One set of units is used for fluids and another for dry goods in the US standard system (e.g., US liquid quart and US dry quart). There is only one set of units for both fluids and dry goods in the imperial system.
