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## Basic geometry and measurement

### Unit 5: Lesson 2

Converting units of mass

# Metric units of mass review (g and kg)

Review the size of grams and kilograms and how to convert between the two.  Then, try some practice problems.

## Metric units of mass

Mass is used to measure the weight of an object. For example, you are measuring the mass of your body when you step on to a scale.
In the metric system of measurement, the most common units of mass are the gram and kilogram.

### How much is a gram?

A small paperclip has a mass of about 1 gram:
A paperclip.

### How much is a kilogram?

A wooden baseball bat has a mass of about 1 kilogram:
A baseball bat.

## Practice set 1: Estimating mass

Problem 1A
Identify the most reasonable unit to measure the mass of a pack of gum.

Want to try more problems like this? Check out this exercise.

## Converting kilograms to grams

1, start text, space, k, i, l, o, g, r, a, m, end text, equals, start color #1fab54, 1000, end color #1fab54, start text, space, g, r, a, m, s, end text
To convert kilograms to grams we multiply the number of kilograms by start color #1fab54, 1, comma, 000, end color #1fab54.
Example:
start color #11accd, 8, end color #11accd, start text, space, k, i, l, o, g, r, a, m, s, end text, equals, start color #11accd, 8, end color #11accd, times, start color #1fab54, 1000, end color #1fab54, equals, start color #11accd, 8, end color #11accd, start color #1fab54, 000, end color #1fab54, start text, space, g, r, a, m, s, end text

## Converting grams to kilograms

1, start text, space, g, r, a, m, end text, equals, start fraction, 1, divided by, start color #1fab54, 1000, end color #1fab54, end fraction, start text, space, k, i, l, o, g, r, a, m, end text
To convert grams to kilograms we divide the number of grams by start color #1fab54, 1000, end color #1fab54.
Example:
start color #ff00af, 9, end color #ff00af, start text, space, g, end text, equals, start fraction, start color #ff00af, 9, end color #ff00af, divided by, start color #1fab54, 1000, end color #1fab54, end fraction, equals, start color #ff00af, 9, end color #ff00af, divided by, start color #1fab54, 1000, end color #1fab54, equals, start color #6495ed, 0, point, 009, end color #6495ed, start text, space, k, g, end text