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### Unit 14: Lesson 4

Converting US Customary units

# 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

InchesFeetYardsMiles
63, comma, 3605, comma, 2801, comma, 760start color #e07d10, 1, end color #e07d10
363start color #e07d10, 1, end color #e07d10start fraction, 1, divided by, 1, comma, 760, end fraction
12start color #e07d10, 1, end color #e07d10start fraction, 1, divided by, 3, end fractionstart fraction, 1, divided by, 5, comma, 280, end fraction
start color #e07d10, 1, end color #e07d10start fraction, 1, divided by, 12, end fractionstart fraction, 1, divided by, 36, end fractionstart 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.

## Practice set 1: Estimating distance

Problem 1A
Identify the most reasonable unit to measure the length of a banana.

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

## 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
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

## Converting smaller units to larger units

1, start text, space, i, n, c, h, end text, equals, start fraction, 1, divided by, start color #28ae7b, 12, end color #28ae7b, end fraction, start text, space, f, o, o, t, end text
1, start text, space, f, o, o, t, end text, equals, start fraction, 1, divided by, start color #28ae7b, 3, end color #28ae7b, end fraction, start text, space, y, a, r, d, end text
1, start text, space, y, a, r, d, end text, equals, start fraction, 1, divided by, start color #28ae7b, 1760, end color #28ae7b, end fraction, start text, space, m, i, l, e, end text
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
1, start text, space, i, n, c, h, end text, equals, start fraction, 1, divided by, start color #28ae7b, 12, end color #28ae7b, end fraction, start text, space, f, o, o, t, end text
start color #ff00af, 72, end color #ff00af, start text, space, i, n, c, h, e, s, end text, equals, start fraction, start color #ff00af, 72, end color #ff00af, divided by, start color #28ae7b, 12, end color #28ae7b, end fraction, equals, start color #ff00af, 72, end color #ff00af, divided by, start color #28ae7b, 12, end color #28ae7b, equals, start color #6495ed, 6, end color #6495ed, start text, space, f, e, e, t, end text
Example: Converting yards to miles
1, start text, space, y, a, r, d, end text, equals, start fraction, 1, divided by, start color #28ae7b, 1760, end color #28ae7b, end fraction, start text, space, m, i, l, e, end text
start color #ff00af, 17, comma, 600, end color #ff00af, start text, space, y, a, r, d, s, end text, equals, start fraction, start color #ff00af, 17, comma, 600, end color #ff00af, divided by, start color #28ae7b, 1760, end color #28ae7b, end fraction, equals, start color #ff00af, 17, comma, 600, end color #ff00af, divided by, start color #28ae7b, 1760, end color #28ae7b, equals, start color #6495ed, 10, end color #6495ed, start text, space, m, i, l, e, s, end text

## Practice set 2: Converting distance units

Problem 2A
Convert.
3 yards equals
inches

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.
• how do i know how much a mile is?
• 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.
• if there is anything smaller than a millimeter would it be like a billionth of a meter
• 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.
• Is there anything smaller than a millemeter
• The micro-, nano-, picto-, and femto- are all prefixes that indicate sizes smaller than the milli-.
• Thank You! this is really helpful but is there a faster way or less confusing way
• I find the metric system is easier and faster, because its all based on tens
• how many yards are in 14 miles
• the answer is 24640 because of 1760 yards in a mile and
1760 x 14 = 24640
• How did they come up with this system of measurement?
• 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.