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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 an ounce?

A slice of bread has a weight of about 1 ounce:
A slice of bread.

How much is a pound?

A soccer ball has a weight of about 1 pound:
A soccer ball.
Want to learn more about customary units of weight? Check out this video.

Practice set 1: Estimating weight

Problem 1A
Identify the most reasonable unit to measure the weight of a refrigerator.
Choose 1 answer:
Choose 1 answer:

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
Want to learn more about converting pounds to ounces? Check out this video.

Practice set 2: Converting units of weight

Problem 2A
Convert.
9 pounds equals
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0, point, 75
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
ounces

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

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