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## 4th grade

### Course: 4th grade > Unit 14

Lesson 7: Converting units of length- Converting metric units of length
- Convert to smaller units (mm, cm, m, & km)
- Converting feet to inches
- Converting yards into inches
- Convert to smaller units (in, ft, yd, & mi)
- Metric units of length review (mm, cm, m, & km)
- US Customary units of length review (in, ft, yd, & mi)

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# Metric units of length review (mm, cm, m, & km)

Review the size of millimeters, centimeters, meters, and kilometers and how to convert between them. Then, try some practice problems.

## Summary of metric units of distance

Kilometer | Meter | Centimeter | Millimeter |
---|---|---|---|

start color #e07d10, 1, end color #e07d10 | 1000 | 100, comma, 000 | 1, comma, 000, comma, 000 |

start fraction, 1, divided by, 1000, end fraction | start color #e07d10, 1, end color #e07d10 | 100 | 1000 |

start fraction, 1, divided by, 100, comma, 000, end fraction | start fraction, 1, divided by, 100, end fraction | start color #e07d10, 1, end color #e07d10 | 10 |

## What is distance?

Distance measures length. For example, the distance of a road is how long the road is.

In the metric system of measurement, the most common units of distance are millimeters, centimeters, meters, and kilometers.

### How big are metric units of distance?

A paper clip is about 1

**millimeter**thick.A fingernail is about 1

**centimeter**wide.The length of a guitar is about 1

**meter**.A

**kilometer**is equal to 1000 meters. It is a little over half of a mile.*Want to learn more about metric units of distance? Check out this video.*

## Converting larger units to smaller units

1, start text, space, c, e, n, t, i, m, e, t, e, r, end text, equals, start color #1fab54, 10, end color #1fab54, start text, space, m, i, l, l, i, m, e, t, e, r, s, end text

1, start text, space, m, e, t, e, r, end text, equals, start color #1fab54, 100, end color #1fab54, start text, space, c, e, n, t, i, m, e, t, e, r, s, end text

1, start text, space, m, e, t, e, r, end text, equals, start color #1fab54, 1, comma, 000, end color #1fab54, start text, space, m, i, l, l, i, m, e, t, e, r, s, end text

1, start text, space, k, i, l, o, m, e, t, e, r, end text, equals, start color #1fab54, 1, comma, 000, end color #1fab54, start text, space, m, e, t, e, r, s, end text

1, start text, space, m, e, t, e, r, end text, equals, start color #1fab54, 100, end color #1fab54, start text, space, c, e, n, t, i, m, e, t, e, r, s, end text

1, start text, space, m, e, t, e, r, end text, equals, start color #1fab54, 1, comma, 000, end color #1fab54, start text, space, m, i, l, l, i, m, e, t, e, r, s, end text

1, start text, space, k, i, l, o, m, e, t, e, r, end text, equals, start color #1fab54, 1, comma, 000, end color #1fab54, start text, space, m, e, t, e, r, s, end text

To convert larger units to smaller units we multiply the number of larger units by the green conversion factor for the appropriate smaller units.

**Example: Converting meters to centimeters:**

1, start text, space, m, e, t, e, r, end text, equals, start color #1fab54, 100, end color #1fab54, start text, space, c, e, n, t, i, m, e, t, e, r, s, end text

start color #11accd, 11, end color #11accd, start text, space, m, e, t, e, r, s, end text, equals, start color #11accd, 11, end color #11accd, times, start color #1fab54, 100, end color #1fab54, equals, start color #11accd, 11, end color #11accd, start color #1fab54, 00, end color #1fab54, start text, space, c, e, n, t, i, m, e, t, e, r, s, end text

start color #11accd, 11, end color #11accd, start text, space, m, e, t, e, r, s, end text, equals, start color #11accd, 11, end color #11accd, times, start color #1fab54, 100, end color #1fab54, equals, start color #11accd, 11, end color #11accd, start color #1fab54, 00, end color #1fab54, start text, space, c, e, n, t, i, m, e, t, e, r, s, end text

## Converting smaller units to larger units

To convert smaller units to larger units we divide the number of smaller units by the purple conversion factor for the appropriate larger units.

**Example: Converting meters to kilometers:**

*Want to learn more about converting between metric units of distance? Check out this video.*

## Practice set 2: Converting distance units

*Want to try more problems like this? Check out these exercises:*

Convert larger units to smaller units

Converting between units

## Want to join the conversation?

- What about micrometers?(33 votes)
- #1, I love the name, #2, A micrometer is 1000 times smaller than a centimeter.(30 votes)

- Is there anything before 'Millimeter' and after 'Kilometer' ?(14 votes)
- technically, as with any SI unit, yes there is.

practically: smaller than milli meter: yes. larger than kilo meter: no

this table shows all the possible prefixes: https://en.wikipedia.org/wiki/Metric_prefix

in physics, you occasionally come across nano meters, one nanometer = 10^-9 meters or 0.000000001 meters

going bigger, you could technically have a mega meter which would be 1000 kilometers, but i have never seen this in practice and most people would misunderstand you (in a metric country)(8 votes)

- Khan is not for nerds it is for people to study(17 votes)
- What is the difference between km and M?(7 votes)
- a km is a kilometer, and an M is a meter. There are 1,000 meters in a kilometer. In other words, one meter is 1/1,000 of a kilometer or 0.001 of a kilometer.(12 votes)

- I get messed up with km to mm.(2 votes)
- Converting from km to m requires multiplying by 1,000, because there are 1,000 m in one km.

Converting m to mm requires multiplying by 1,000, because there are 1,000 mm in one m.

It follows from these two facts that converting from km to mm requires multiplying by 1,000*1,000=1,000,000.

Have a blessed, wonderful day!(22 votes)

- How many millimeters are in 5 meters?(6 votes)
- Okay so if y'all don't get this, let me give you an example. So, 1 kilogram = 1,000 grams, right? So, if the question asks you how many grams are 4 kilograms, you multiply 4 by 1,000 which is 4,000. Because if 1 kilogram = 1,000 grams, 4 must be 4,000 grams.(10 votes)
- thanks btw also if i understood ur so kind(3 votes)

- I have one tree that is 4 meters tall a second tree that is 3 m tall how many centimeters taller is the first tree(4 votes)
`100 cm is the answer`

(13 votes)

- Is there such thing as a decimeter?(6 votes)
- Yes! A decimeter is 1/10 of a meter. This also means a decimeter is 10 centimeters, and a decimeter is 100 millimeters.(10 votes)

- if two vegans are arguing is it still considered beef?🤔🤔(8 votes)
- no its called cow(5 votes)