Units of Weight

There are 2 main units of customary weight: How Heavy is it? There are 2 main units of customary weight: Pounds Ounces

Ounces are used to weigh light things A letter is about an ounce.

Pounds are used to weigh heavy things Your Open Court book weighs about a pound.

The abbreviation for pound is lb. The baby weighs 15 lbs.

The abbreviation for ounce is oz. The pencil weighs about 5 oz.

Conversions 1 lb = 16 oz. One way to remember is that lb sort of looks like 16! lb 16

Tom had 4 lbs. of fruit. Sam had 36 oz. of fruit. Who had more? Step 1: What do I know? I know that they both need to be the same unit because I can’t compare different units.

Step 2: Choose the lower unit and convert. Since there are oz and pounds, ounces are the smaller unit. I will convert to ounces.

Since I know that 1 lb = 16 oz, I can make a table. pounds 1 ounces 16

pounds 1 2 3 4 ounces 16 32 48 64 4 pounds is equal to 64 oz.

Tom had 4 lbs. of fruit. Sam had 36 oz. of fruit. Who had more? Since 4 pounds = 64 oz, then Tom had more, because 64 oz > 36 oz.

Since 16 oz is one pound, then… I can also DRAW A PICTURE to convert measurement. Since 16 oz is one pound, then… 16 oz 16 oz 16 oz 16 oz 16 + 16 + 16 + 16 = 64 OR 4 x 16 = 64

Metric Measurements Gram—used for light items A paper clip is about a gram.

Kilogram—used for bigger things Your math book is about a kilogram.

Abbreviations Gram g Kilograms kg Remember…1,000 g = 1 kg

Conversions Convert to lowest measure… Grams! Mary needed 5,000 g of flour for the recipe. She had a bag of 4 kg. Does she have enough? Convert to lowest measure… Grams!

Draw a Picture! Since 1 kg = 1,000 g, then 4 kg = 4,000g 1,000 g

So…she does not have enough. She only has 4,000 kg! Mary needed 5,000 g of flour for the recipe. She had a bag of 4 kg. Does she have enough? So…she does not have enough. She only has 4,000 kg!