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Converting units of measurement: FAQ

Frequently asked questions about converting units of measurement.

What are some of the main forms of measurement?

We can categorize measurement into three categories:
  • Weight/mass: grams, kilograms, ounces, pounds
  • Volume: milliliters, liters, cups, pints, quarts, gallons
  • Length/distance: millimeters, centimeters, meters, kilometers, inches, feet, yards, miles

How do we convert metric units?

To convert metric units, we use the prefixes: kilo-, hecto-, deka-, deci-, centi-, and milli-. Each prefix corresponds to a certain power of ten. For example, 1 kilometer (km) is equal to 1,000 meters (m), and 1 centimeter (cm) is equal to 0.01 meters (m).
Try it yourself with this exercise:

How do we convert US customary units?

To convert US customary units, we need to know the relationships between the different units. For example, there are 12 inches in 1 foot, 3 feet in 1 yard, and 16 ounces in 1 pound.
Try it yourself with this exercise:

What are some common mistakes people make when converting units?

Some common mistakes people make when converting units include not knowing the relationships between the different units, not using the correct conversion factor, and not keeping track of the units throughout the calculation.

What are some real-world applications of unit conversions?

Unit conversions are used in a wide variety of fields, such as science, engineering, manufacturing, and cooking. For example, when working with measurements in a lab, scientists often need to convert between metric and US customary units. And when cooking, we might need to convert a recipe from cups to milliliters in order to use the correct proportions.
Try it yourself with these exercises:

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