U.S. Customary System Unit Multipliers Lesson 23

When we attach words to numbers, we call the combination a denominate number where the words are the units. The units of the denominate number, 4 feet are feet.

The Customary System is used as the basic unit of measurement in the United States. The basic units of the Customary System are the inch, foot, yard, and mile.

Length Equivalents 12 inches (in.) = 1 foot (ft.) 3 feet (ft.) = 1 yard (yd.) 5280 feet (ft) = 1 mile (mi.)

Weight Equivalents The basic unit of weight are the ounce, pound, and ton. 16 ounces (oz.) = 1 pound (lb.) 2000 pounds (lbs.) = 1 ton

Liquid Equivalents 8 fluid ounces (fl. oz.) = 1 cup ( c) 2 cup ( c) = 1 pint (pt) 2 pint (pt) = 1 quart (qt) 4 quarts (qt) = 1 gallon (gal)

Unit Multipliers Unit Multipliers are fractions that have a denominator with an equal value as its numerator. For example, unit multipliers would include: 12 in. 1 yd 5280 ft 12 in. 1 yd 5280 ft 1 ft. 3 ft. 1 mi. 1 ft. 3 ft. 1 mi.

We can use unit multipliers to convert one unit of measurement to another. This will change the unit without changing the value.

For example To convert 5 feet to inches, we use the unit multiplier that has the relationship between feet and inches. 5 ft x 12 in = 60 in 5 ft x 12 in = 60 in 1 1 ft 1 1 ft

Example Use unit multipliers to convert 420 feet to yards

Example Use unit multipliers to convert 72 inches to feet

Multiple Unit Multipliers Convert 360 inches to yards

Answer We will first convert inches to feet and then the feet to yards. 360 in. x 1 ft. x 1 yd = 360 = 10 yd 12 in. 3 ft. (12)(3) 12 in. 3 ft. (12)(3)

Example Convert 48 gallons to cups

Answer 48 gal x 4 qts. x 2 pt. x 2 cups = (48)(4)(2)(2) 1 gal 1 qt. 1 pint 1 1 gal 1 qt. 1 pint cups 768 cups

Approximations Between System Lengths 1 inch ≈ 2.5 centimeters 1 centimeter ≈ 0.4 inch 1 yard ≈ 0.9 meter 1 meter ≈ 1.1 yards 1 mile ≈ 1.6 kilometers 1 kilometer ≈ 0.6 mile

Approximate Conversions Between System Units of Weight & Mass 1 ounce ≈ 28 grams 1 pound ≈ 0.45 kilogram 1 kilogram ≈ 2.2 pounds 1 ton ≈ 0.9 metric ton 1 metric ton ≈ 1.1 tons

Approximate Conversions Between System Units of Capacity 1 quart ≈ 0.95 liter 1 liter ≈ 1.05 quart

Examples Which is longer: 40 centimeters or 1.5 feet? How much longer? A Rottweiler weighs 128 pounds. What is the weight in kilograms? Approximately how many milliliters are equal to 1 fluid ounce?

Try It Yourself! A football player has a mass of 125 kilograms. Approximately what is the player’s weight in pounds?

Temperature The unit of temperature in the U.S. Customary System is degrees Fahrenheit. The unit of temperature in the metric system is degrees Celsius.

Temperature U.S. Customary System MetricSystem Water freezes 32 ºF 0 ºC Room temperature 72 ºF 22.2 ºC Normal human body temp ºF 37 ºC Water boils 212 ºF 100 ºC

Temperature To convert from degrees Celsius to degrees Fahrenheit, use the following formula: ºF = (9/5 · ºC) + 32 To convert from degrees Fahrenheit to degrees Celsius use: ºC = 5/9(ºF – 32) ºC = 5/9(ºF – 32)

Homework fl. oz. = ________ qt oz. = ________ lbs yd = ________ in ,960 ft = _______ mi T = ________ oz c = ________ qt

Homework m = _______ mm kg = _______ mg 3. 3,400 L = _______ kL cm = _______ hm

Homework kg = ________ lbs qt = ________ L 3. 6 in = ________ cm 4. 7 fl oz = _______ mL 5. Patrick weighs 147 pounds. How many kilograms does Patrick weigh?

Homework ºC = _______ºF ºF = _______ ºC ºC = _______ ºF 4. The melting point of zinc is 787 ºF. What is the melting point of zinc in ºC? 5. A recipe says that cookies should be baked at 180 ºC. What is the temperature in ºF?