9.2 Measuring Area and Volume

Area Area is measured in square units Area can be found be counting the number of square units 1 unit A = 1 square unit 1 unit A = 12 square units

Square units of measure 1 square foot (ft2) = 144 square inches (in2) 1 square yard (yd2) = 9 square feet (ft2) 1 acre (a) = 43,560 square feet (ft2) or 4,840 square yard (yd2) 1 square mile (mi2) = 640 acres

Population density Population density is the population of a region divided by the area of the region population density = Example: The population of Berkeley, CA is 103,000 and its area is 5.1 (mi2). What is the population density?

Example: find the population density The population of Alaska is 494,423 and the area is 97,818 (mi2).

English/metric equivalents A hectare is the metric equivalent of an acre. It is approximately 2 football fields side by side. 1 acre = 0.4 hectare (ha) Example: A property in Italy sells for $545,000 for 6.8 hectares. What is the price per acre?

Volume Volume is measure in cubic units 1 cubic yard =27 cubic feet 1 cubic foot = 1728 cubic inches

Capacity Capacity is the amount of fluid a 3D object can hold 2 pints (pts)= 1 quart(qts) 4 quarts = 1 gallon (gal) 1 gallon = 128 ounces (oz) 1 cup = 8 ounces

Volume and capacity 1 cubic yard = 200 gal (approximate) 1 cubic feet = 7.48 gal 231 cubic inches = 1 gal

Example A swimming pool has a volume of 22,500 cubic feet. How many gallons of water can it hold? A water tank has a volume of 8 cubic yards. How many gallons of water can it hold?

Metric Capacity The basic metric unit is the liter (L) 1 liter = 1.0567 quarts Volume = Metric Capacity 1 cm3 = 1 mL 1000 cm3 = 1 L 1 m3 = 1 kL 1 dm3 =1 L

Example An aquarium holds 36,000 cm3. How many liters does it hold?

Hw: p. 477/1-36,45-48