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

Want to join the conversation?

  • duskpin ultimate style avatar for user 295071
    how does 8tons = 16000
    (10 votes)
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  • piceratops seedling style avatar for user PVZ2 CHOMPER PEASHOOTER
    We're no strangers to love
    You know the rules and so do I (do I)
    A full commitment's what I'm thinking of
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    We've known each other for so long
    Your heart's been aching, but you're too shy to say it (say it)
    Inside, we both know what's been going on (going on)
    We know the game and we're gonna play it
    And if you ask me how I'm feeling
    Don't tell me you're too blind to see
    Never gonna give you up
    Never gonna let you down
    Never gonna run around and desert you
    Never gonna make you cry
    Never gonna say goodbye
    Never gonna tell a lie and hurt you
    Never gonna give you up
    Never gonna let you down
    Never gonna run around and desert you
    Never gonna make you cry
    Never gonna say goodbye
    Never gonna tell a lie and hurt you
    We've known each other for so long
    Your heart's been aching, but you're too shy to say it (to say it)
    Inside, we both know what's been going on (going on)
    We know the game and we're gonna play it
    I just wanna tell you how I'm feeling
    Gotta make you understand
    Never gonna give you up
    Never gonna let you down
    Never gonna run around and desert you
    Never gonna make you cry
    Never gonna say goodbye
    Never gonna tell a lie and hurt you
    Never gonna give you up
    Never gonna let you down
    Never gonna run around and desert you
    Never gonna make you cry
    Never gonna say goodbye
    Never gonna tell a lie and hurt you
    Never gonna give you up
    Never gonna let you down
    Never gonna run around and desert you
    Never gonna make you cry
    Never gonna say goodbye
    Never gonna tell a lie and hurt you

    pls upvote
    (8 votes)
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  • mr pink red style avatar for user Welcome back Mallory!
    how do I know if I need to multiply or dived?
    (3 votes)
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    • starky ultimate style avatar for user Slaga Lika
      To convert "bigger" units to "smaller" ones, you multiply.
      To convert "smaller" to bigger, you divide.
      Pound is something big, and ounce is something small - smaller parts make one big thing - 16 ounces are in a pound.
      To convert pounds to ounces, you multiply by 16.
      To convert ounces to pounds, you divide by 16.
      (10 votes)
  • blobby green style avatar for user WyattN
    open da noor
    (7 votes)
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  • starky tree style avatar for user Jax.Beavers
    55+55=?
    (4 votes)
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  • duskpin seedling style avatar for user AlinaR
    how many ounces in a pound? I am braindead:/
    (2 votes)
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  • starky tree style avatar for user Keeley Krasniak
    ░░░░░░░░░▄░░░░░░░░░░░░░░▄░░░░
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    (4 votes)
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  • stelly blue style avatar for user sturtza697
    Why is it called U.S Customary Units of Weight?
    (3 votes)
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  • stelly yellow style avatar for user floraredberry
    What is the difference between weight and mass?
    (1 vote)
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    • aqualine ultimate style avatar for user Shall Win
      Weight and mass are used interchangeably, but they don't mean the same thing.
      Mass is the amount of matter in an object, while weight is the force of gravity by which the earth attracts towards it.

      So your mass on Jupiter and Earth would be the same, but your weight would be different. But in math levels right now, you can use them interchangeably.
      (6 votes)
  • hopper cool style avatar for user RobloxianIzzy {Currently online}
    Seems like most of you are with me. I din't get this either. =(
    (3 votes)
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