1. 9.2 Measuring Area and Volume

2. 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

3. 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

4. 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?

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

6. 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?

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

8. 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

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

10. 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?

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

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

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