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Lesson 1: Estimating mass

# Units of measurement: FAQ

## Why do we need to learn how to estimate mass, volume, and length?

Estimating measurements is a valuable skill in many everyday situations. For example, when you're cooking, you might need to eyeball how much of an ingredient to add. Or when you're packing for a trip, you might need to guess how much your suitcase weighs so you don't go over the airline's weight limit.
Try it yourself with these exercises:

## 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 between different units of measurement?

There are formulas you can use to convert between different units of measurement. For example, to convert kilograms to grams, you multiply the number of kilograms by 1, comma, 000. To convert pounds to ounces, you multiply the number of pounds by 16.
Conversions
1 kilometer equals, 1, comma, 000 meters1 minute equals, 60 seconds1 literequals, 1, comma, 000 milliliters
1 meter equals, 100 centimeter1 hour equals, 60 minutes1 kilogram equals, 1, comma, 000 grams
1 meter equals, 1, comma, 000 millimeters1 gram equals, 1, comma, 000 milligrams
1 centimeter equals, 10 millimeters
Try it yourself with these exercises:

## How do we use these skills in the real world?

There are countless ways we use these skills in the real world! We use measurement to cook, build, and design things. We use time-telling skills to keep ourselves on schedule, and we use currency conversion skills when we travel to different countries.