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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 $1,000$. To convert pounds to ounces, you multiply the number of pounds by $16$.
Conversions
$1$ kilometer $=1,000$ meters$1$ minute $=60$ seconds$1$ liter$=1,000$ milliliters
$1$ meter $=100$ centimeter$1$ hour $=60$ minutes$1$ kilogram $=1,000$ grams
$1$ meter $=1,000$ millimeters$1$ gram $=1,000$ milligrams
$1$ centimeter $=10$ 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.

## Want to join the conversation?

• what is a measurement

PS. I'm asking for my mom
• In math, by measure, we mean quantifying the length, weight, capacity (volume), and many more quantities. Measurement of any quantity is expressed in 2 parts— a numeric value and the specific unit. The following are the most measured quantities: Length. Weight.
• How heavy is earth?
• The Earth is extremely heavy, with a mass of about 6,000,000,000,000,000,000,000,000 kilograms! In scientific notation, this is 6 x 10^24 kilograms.

Have a blessed, wonderful day!
• why do we have to use the metric system?!?! we live in U.S.!?!?!?
• A lot of science uses metric. The benefit of using metric is because of it's simpler conversions, so that's why a lot of researchers or scientists use metric. Also trust me, if you want to tell a foreigner some measurements it's better to use metric, because only 3 nations out of 193 UN member nations use some form of the imperial system.

Hope that clarifies it.
• Is this all the units of measurement we need? and how many units of measurement there are?
• Probably thousands also that is what most people use.
• how do you do area and perimeter?
• so area is the inside so you do like x_= but in 2 sides are one length and the other 2 are another length so you add for exaple +_=
• Why can't the U.S.A. be metric?
• I wish it was. But, unfortunately they be been using this system for so long that it would be too complicated to switch to metric.