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## 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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# US Customary units of length review (in, ft, yd, & mi)

Review the size of inches, feet, yards, and miles and how to convert between them. Then, try some practice problems.

## Summary of customary units of distance

Inches | Feet | Yards | Miles |
---|---|---|---|

63, comma, 360 | 5, comma, 280 | 1, comma, 760 | start color #e07d10, 1, end color #e07d10 |

36 | 3 | start color #e07d10, 1, end color #e07d10 | start fraction, 1, divided by, 1, comma, 760, end fraction |

12 | start color #e07d10, 1, end color #e07d10 | start fraction, 1, divided by, 3, end fraction | start fraction, 1, divided by, 5, comma, 280, end fraction |

start color #e07d10, 1, end color #e07d10 | start fraction, 1, divided by, 12, end fraction | start fraction, 1, divided by, 36, end fraction | start fraction, 1, divided by, 63, comma, 360, end fraction |

## What is distance?

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

In the US customary system of measurement, the most common units of distance are inches, feet, yards, and miles.

### How big are customary units of distance?

The length of a quarter is about 1

**inch**.The length of a man's shoe is about 1

**foot**.The length of a guitar is about 1

**yard**.The length of a runway at a large airport is about 1

**mile**.*Want to learn more about customary units of distance? Check out this video.*

## Converting larger units to smaller units

1, start text, space, f, o, o, t, end text, equals, start color #1fab54, 12, end color #1fab54, start text, space, i, n, c, h, e, s, end text

1, start text, space, y, a, r, d, end text, equals, start color #1fab54, 3, end color #1fab54, start text, space, f, e, e, t, end text

1, start text, space, y, a, r, d, end text, equals, start color #1fab54, 36, end color #1fab54, start text, space, i, n, c, h, e, s, end text

1, start text, space, m, i, l, e, end text, equals, start color #1fab54, 1760, end color #1fab54, start text, space, y, a, r, d, s, end text

1, start text, space, y, a, r, d, end text, equals, start color #1fab54, 3, end color #1fab54, start text, space, f, e, e, t, end text

1, start text, space, y, a, r, d, end text, equals, start color #1fab54, 36, end color #1fab54, start text, space, i, n, c, h, e, s, end text

1, start text, space, m, i, l, e, end text, equals, start color #1fab54, 1760, end color #1fab54, start text, space, y, a, r, d, 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 feet to inches**

1, start text, space, f, o, o, t, end text, equals, start color #1fab54, 12, end color #1fab54, start text, space, i, n, c, h, e, s, end text

start color #11accd, 5, end color #11accd, start text, space, f, e, e, t, end text, equals, start color #11accd, 5, end color #11accd, times, start color #1fab54, 12, end color #1fab54, equals, 60, start text, space, i, n, c, h, e, s, end text

start color #11accd, 5, end color #11accd, start text, space, f, e, e, t, end text, equals, start color #11accd, 5, end color #11accd, times, start color #1fab54, 12, end color #1fab54, equals, 60, start text, space, i, n, c, h, e, 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 green conversion factor for the appropriate larger units.

**Example: Converting inches to feet**

**Example: Converting yards to miles**

*Want to learn more about converting between customary 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?

- the fastest way to find how many in in a mile is to find how many feet are in mile and multiply that by 12.(15 votes)
- how do i know how much a mile is?(6 votes)
- This is something that you will probably want to memorize. A mile is 5280 feet.

Once you have that in your memory, you can then use math to determine how many yards a mile is and all sorts of other measurements.(13 votes)

- if there is anything smaller than a millimeter would it be like a billionth of a meter(8 votes)
- millimeter = 1/1,000 meter.

micrometer = 1/1,000,000 meter.

nanometer = 1/1,000,000,000 meter.

and there is no limit to how many units there should be. whenever we find a length in the real world that we need to express a lot of times and we don't have a unit that's close to this length, we can create a new unit of length.(0 votes)

- Is there anything smaller than a millemeter(6 votes)
- The micro-, nano-, picto-, and femto- are all prefixes that indicate sizes smaller than the milli-.(8 votes)

- Thank You! this is really helpful but is there a faster way or less confusing way(6 votes)
- I find the metric system is easier and faster, because its all based on tens(4 votes)

- how many yards are in 14 miles(7 votes)
- the answer is 24640 because of 1760 yards in a mile and

1760 x 14 = 24640(5 votes)

- How did they come up with this system of measurement?(8 votes)
- I am from Australia and never use "miles" for driving, converting or just about ANYTHING!

Anything I should know about when using miles for anything?

Thanks, sincerely Patrick.(5 votes)- uh miles are the same thing as kilo i think btw why u so formal(2 votes)

- how is 98 cups = to 49 pints.(6 votes)
- if there are two cups in one pint, and you have 49 pints you would do 49 x 2 which is 98.(3 votes)

- I am so lost i need help.(5 votes)