Customary Units

Units of Length

• Inch (in)
• Foot (ft): 12 inches
• Yard (yd): 3 feet
• Mile (mi): 1,760 yards or 5,280 feet

Units of Liquid Volume

• Fluid Ounce (fl oz)
• Cup (c): 8 fl oz
• Pint (pt): 2 cups
• Quart (qt): 2 pints
• Gallon (gal): 4 quarts

Units of Weight

• Ounce (oz)
• Pound (lb): 16 ounces
• Ton (T): 2,000 pounds

Perimeter

The distance around a shape (measured in units of length, e.g. ft, in).

Area

The amount of surface a shape covers (square inches, square feet, etc.).

Volume of a Solid

The amount of space a solid occupies (cubic inches, cubic feet, etc.).

Time

• 60 seconds = 1 minute
• 60 minutes = 1 hour
• 24 hours = 1 day
• 7 days = 1 week

Temperature

• Measured in degrees Fahrenheit (°F)

Metric Units

Units of Length

• Millimeter (mm)
• Centimeter (cm): 10 mm
• Meter (m): 100 cm
• Kilometer (km): 1,000 m

Units of Liquid Volume

• Milliliter (mL)
• Liter (L): 1,000 mL

Units of Mass

• Milligram (mg)
• Gram (g): 1,000 mg
• Kilogram (kg): 1,000 g

Perimeter, Area, and Volume

• Perimeter: measured in meters, centimeters, etc.
• Area: measured in square meters (m²), square centimeters (cm²), etc.
• Volume: measured in cubic meters (m³), cubic centimeters (cm³), etc.

Unit Conversions

Customary to Metric

• 1 inch ≈ 2.54 cm
• 1 foot ≈ 0.3048 m
• 1 mile ≈ 1.609 km
• 1 ounce ≈ 28.35 g
• 1 pound ≈ 0.4536 kg
• 1 gallon ≈ 3.785 L
• °F to °C: (°F - 32) × 5/9

Metric to Customary

• 1 cm ≈ 0.3937 in
• 1 m ≈ 3.281 ft
• 1 km ≈ 0.6214 mi
• 1 g ≈ 0.03527 oz
• 1 kg ≈ 2.205 lb
• 1 L ≈ 0.2642 gal
• °C to °F: (°C × 9/5) + 32

Examples

• Customary Length: 3 feet = 36 inches
• Metric Length: 1.5 meters = 150 centimeters
• Customary Volume: 2 quarts = 4 pints
• Metric Volume: 0.75 liters = 750 milliliters
• Customary Weight: 3 pounds = 48 ounces
• Metric Mass: 2.5 kg = 2,500 g
• Perimeter: Rectangle 4 cm × 6 cm: 2(4+6) = 20 cm
• Area: Square with 5 m sides: 5 × 5 = 25 m²
• Volume: Box 2 m × 3 m × 4 m: 2 × 3 × 4 = 24 m³
• Conversion: 10 inches × 2.54 = 25.4 cm
• Temperature: 20°C = (20 × 9/5) + 32 = 68°F

Questions and Answers