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Lesson 5: Converting units of mass

# US Customary units of weight review (oz & lb)

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

## Customary units of weight

Weight is a quantity of heaviness. For example, you are measuring the weight of your body when you step on to a scale.
In the customary system of measurement, the most common units of weight are the ounce (oz) and pound (lb).

### How much is a pound?

A soccer ball has a weight of about 1 pound:

## Practice set 1: Estimating weight

Problem 1A
• Current
Identify the most reasonable unit to measure the weight of a refrigerator.

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

## Converting pounds to ounces

1, start text, space, p, o, u, n, d, end text, equals, start color #28ae7b, 16, end color #28ae7b, start text, space, o, u, n, c, e, s, end text
To convert pounds to ounces we multiply the number of pounds by start color #1fab54, 16, end color #1fab54.
Example:
start color #ff00af, 30, end color #ff00af, start text, space, p, o, u, n, d, s, end text, equals, start color #ff00af, 30, end color #ff00af, times, start color #28ae7b, 16, end color #28ae7b, equals, start color #6495ed, 480, end color #6495ed, start text, space, o, u, n, c, e, s, end text

## Converting ounces to pounds

1, start text, space, o, u, n, c, e, end text, equals, start fraction, 1, divided by, start color #28ae7b, 16, end color #28ae7b, end fraction, start text, space, p, o, u, n, d, end text
To convert ounces to pounds we divide the number of ounces by start color #1fab54, 16, end color #1fab54.
Example:
start color #ff00af, 112, end color #ff00af, start text, space, o, u, n, c, e, s, end text, equals, start fraction, start color #ff00af, 112, end color #ff00af, divided by, start color #28ae7b, 16, end color #28ae7b, end fraction, equals, start color #ff00af, 112, end color #ff00af, divided by, start color #28ae7b, 16, end color #28ae7b, equals, start color #6495ed, 7, end color #6495ed, start text, space, p, o, u, n, d, s, end text

## Practice set 2: Converting units of weight

Problem 2A
• Current
Convert.
9 pounds equals
ounces

Want to try more problems like this? Check out these exercises:
Convert larger units to smaller units
Converting between units