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Laura gave birth to triplets weighing 3 pounds 3 ounces, 3 pounds 3 ounces, and 2 pounds 9 ounces. What was the total birth weight of the three babies?
$\text{9 lbs}.\phantom{\rule{0.2em}{0ex}}\text{8 oz}$
Stan cut two pieces of crown molding for his family room that were 8 feet 7 inches and 12 feet 11 inches. What was the total length of the molding?
21 ft. 6 in.
Anthony bought four planks of wood that were each 6 feet 4 inches long. What is the total length of the wood he purchased?
We will multiply the length of one plank to find the total length.
Multiply the inches and then the feet.  
Convert the 16 inches to feet.
Add the feet. 

Anthony bought 25 feet and 4 inches of wood. 
Henri wants to triple his spaghetti sauce recipe that uses 1 pound 8 ounces of ground turkey. How many pounds of ground turkey will he need?
4 lbs. 8 oz.
Joellen wants to double a solution of 5 gallons 3 quarts. How many gallons of solution will she have in all?
11 gallons 2 qt.
In the metric system , units are related by powers of 10. The roots words of their names reflect this relation. For example, the basic unit for measuring length is a meter. One kilometer is 1,000 meters; the prefix kilo means thousand . One centimeter is $\frac{1}{100}$ of a meter, just like one cent is $\frac{1}{100}$ of one dollar.
The equivalencies of measurements in the metric system are shown in [link] . The common abbreviations for each measurement are given in parentheses.
Metric System of Measurement  

Length  Mass  Capacity 
1 kilometer (km) = 1,000 m
1 hectometer (hm) = 100 m 1 dekameter (dam) = 10 m 1 meter (m) = 1 m 1 decimeter (dm) = 0.1 m 1 centimeter (cm) = 0.01 m 1 millimeter (mm) = 0.001 m 
1 kilogram (kg) = 1,000 g
1 hectogram (hg) = 100 g 1 dekagram (dag) = 10 g 1 gram (g) = 1 g 1 decigram (dg) = 0.1 g 1 centigram (cg) = 0.01 g 1 milligram (mg) = 0.001 g 
1 kiloliter (kL) = 1,000 L
1 hectoliter (hL) = 100 L 1 dekaliter (daL) = 10 L 1 liter (L) = 1 L 1 deciliter (dL) = 0.1 L 1 centiliter (cL) = 0.01 L 1 milliliter (mL) = 0.001 L 
1 meter = 100 centimeters
1 meter = 1,000 millimeters 
1 gram = 100 centigrams
1 gram = 1,000 milligrams 
1 liter = 100 centiliters
1 liter = 1,000 milliliters 
To make conversions in the metric system, we will use the same technique we did in the US system. Using the identity property of multiplication, we will multiply by a conversion factor of one to get to the correct units.
Have you ever run a 5K or 10K race? The length of those races are measured in kilometers. The metric system is commonly used in the United States when talking about the length of a race.
Nick ran a 10K race. How many meters did he run?
We will convert kilometers to meters using the identity property of multiplication.
10 kilometers  
Multiply the measurement to be converted by 1.  
Write 1 as a fraction relating kilometers and meters.  
Simplify.  
Multiply.  10,000 meters 
Nick ran 10,000 meters. 
Sandy completed her first 5K race! How many meters did she run?
5,000 meters
Herman bought a rug 2.5 meters in length. How many centimeters is the length?
250 centimeters
Eleanor’s newborn baby weighed 3,200 grams. How many kilograms did the baby weigh?
We will convert grams into kilograms.
Multiply the measurement to be converted by 1.  
Write 1 as a function relating kilograms and grams.  
Simplify.  
Multiply.  $\frac{\text{3,200 kilograms}}{\mathrm{1,000}}$ 
Divide.  3.2 kilograms
The baby weighed 3.2 kilograms. 
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