Standards of Measure
Standards of Measure
This lesson discusses the conversion within and between the standard system and the metric system and between 12-hour clock time and military time.
Length Conversions
The basic units of measure of length in the standard measurement system are inches, feet, yards, and miles. There are 12 inches (in.) in 1 foot (ft.), 3 feet (ft.) in 1 yard (yd.), and 5,280 feet (ft.) in 1 mile (mi.).
The basic unit of measure of metric length is meters. There are 1,000 millimeters (mm), 100 centimeters (cm), and 10 decimeters (dm) in 1 meter (m). There are 10 meters (m) in 1 dekameter (dam), 100 meters (m) in 1 hectometer (hm), and 1,000 meters (m) in 1 kilometer (km).
To convert from one unit to the other, multiply by the appropriate factor.
Be Careful
There are some cases where multiple conversions must be performed to determine the correct units.
Length Conversions Review
Volume and Weight Conversions
There are volume conversion factors for standard and metric volumes.
The volume conversions for standard volume are shown in the table.
| Measurement | Conversion |
| Pints (pt.) and fluid ounces (fl. oz.) | 1 pint equals 16 fluid ounces |
| Quarts (qt.) and pints (pt.) | 1 quart equals 2 pints |
| Quarts (qt.) and gallons (gal.) | 1 gallon equals 4 quarts |
The basic unit of volume for the metric system is liters. There are 1,000 milliliters (mL) in 1 liter (L) and 1,000 liters (L) in 1 kiloliter (kL).
There are weight conversion factors for standard and metric weights.
The basic unit of weight for the standard measurement system is pounds. There are
16 ounces (oz.) in 1 pound (lb.) and
2,000 pounds (lb.) in 1 ton (T).
Keep In Mind
The conversions within the metric system are multiples of 10.
The basic unit of weight for the metric system is grams.
| Measurement | Conversion |
| Milligrams (mg) and grams (g) | 1,000 milligrams equals 1 gram |
| Centigrams (cg) and grams (g) | 100 centigrams equals 1 gram |
| Kilograms (kg) and grams (g) | 1 kilogram equals 1,000 grams |
| Metric tons (t) and kilograms (kg) | 1 metric ton equals 1,000 kilograms |
Volume and Weight Conversions Review
Conversions between Standard and Metric Systems
The table shows the common conversions of length, volume, and weight between the standard and metric systems.
| Measurement | Conversion |
| Centimeters (cm) and inches (in.) | 2.54 centimeters equals 1 inch |
| Meters (m) and feet (ft.) | 1 meter equals 3.28 feet |
| Kilometers (km) and miles (mi.) | 1.61 kilometers equals 1 mile |
| Quarts (qt.) and liters (L) | 1.06 quarts equals 1 liter |
| Liters (L) and gallons (gal.) | 3.79 liters equals 1 gallon |
| Grams (g) and ounces (oz.) | 28.3 grams equals 1 ounce |
| Kilograms (kg) and pounds (lb.) | 1 kilogram equals 2.2 pounds |
There are many additional conversion factors, but this lesson uses only the common ones. Most factors have been rounded to the nearest hundredth for accuracy.
STEP BY STEP
Step 1. Choose the appropriate conversion factor within each system, if necessary.
Step 2. Choose the appropriate conversion factor from the standard and metric conversion.
Step 3. Multiply and simplify to the nearest hundredth.
Conversions between Standard and Metric Systems Review
Time Conversions
Two ways to keep time are 12-hour clock time using a.m. and p.m. and military time based on a 24-hour clock. Keep these three key points in mind:
- The hours from 1:00 a.m. to 12:59 p.m. are the same in both methods. For example, 9:15 a.m. in 12-hour clock time is 0915 in military time.
- From 1:00 p.m. to 11:59 p.m., add 12 hours to obtain military time. For example, 4:07 p.m. in 12-hour clock time is 1607 in military time.
- From 12:01 a.m. to 12:59 a.m. in 12-hour clock time, military time is from 0001 to 0059.
Keep In Mind
Midnight (12:00 a.m.) is 2400 or 0000 in military time.
Time Conversions Review
Temperature Conversions
Temperatures can be written using the Fahrenheit English system or the Celsius metric system. The Fahrenheit temperature scale is part of the English system which bases the freezing point of water off of 32°F and the boiling point of water as 212°F. Water freezes at 0°C and 100°C in the metric system.
While these topics are covered in further depth within the sciences, it is important to know that formulas help convert between the two systems. The following formulas are used to convert temperatures:
| \(°C =\frac{5}{9}(°F – 32)\) | \(°F =(°C\times\frac{9}{5})+ 32\) |
It is helpful to recall the order of operations in order to convert temperatures. Consider the following examples:
This material is covered in further depth within the science section.
Please refer to our video in “Temperature” underneath the science tab for further instruction.
Let’s Review!
- To convert from one unit to another, choose the appropriate conversion factors.
- In many cases, it is necessary to use multiple conversion factors.
| Metric | English |
| Volume | |
| 1 cubic centimeter = 1 milliliter | 30 milliliters = 1 ounce |
| 1,000 milliliters = 1 liter | 8 ounces = 1 cup |
| 2 cups = 1 pint | |
| 2 pints = 1 quart | |
| 4 quarts = 1 gallon | |
| Weight | |
| 1,000 milligrams = 1 gram | 16 ounces = 1 pound |
| 100 centigrams = 1 gram | 2.2 pounds = 1 kilogram |
| 1,000 grams = 1 kilogram | 2,000 pounds = 1 ton |
| 1,000 kilograms = 1 ton | |
| Distance | |
| 10 millimeters = 1 centimeter | 12 inches = 1 foot |
| 2.54 centimeters = 1 inch | 3 feet = 1 yard |
| 100 centimeters = 1 meter | 5, 280 feet = 1,760 yards = 1 mile |
| 1,000 meters = 1 kilometer |
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