conversions

Introduction

  • Lesson focuses on American units and conversions.
  • Goal: Convert between American units of measure.
  • The United States customary system is the measurement system used in the U.S., which is unique as it is the only industrialized nation that does not predominantly use the metric system in its commercial activities.
  • The metric system is widely utilized in science, medicine, government, and various industrial sectors.

Overview of Conversions

Types of Conversions

  • Length
  • Capacity
  • Weight
  • Time

Conversion Methods

  1. Multiplying and Dividing
    • Multiply when converting from a large unit to a smaller unit.
    • Divide when converting from a smaller unit to a larger unit.
  2. Using Unit Fractions
    • Each unit fraction must equal one.
    • The numerator contains the desired measurement unit for the answer.
    • The denominator contains the unit to be changed.

Example Conversions

Length Conversion: Inches to Feet

  1. Convert 45 inches to feet.
    • Write it in fraction form: 45 inches1\frac{45\text{ inches}}{1}
    • Multiply by a unit fraction:
    • Relationship: 1 foot=12 inches1\text{ foot} = 12\text{ inches}
    • Setup unit fraction:
      • 1 foot12 inches\frac{1\text{ foot}}{12\text{ inches}}
    • Simplification:
      • inches\text{inches} cancels out.
    • Calculation:
      • Numerator: 45×1 foot=45 feet45 \times 1\text{ foot} = 45\text{ feet}
      • Denominator: 1×12=121 \times 12 = 12
    • Final result:
      • 4512 feet=3.75 feet\frac{45}{12} \text{ feet} = 3.75\text{ feet}

Length Conversion: Miles to Yards

  1. Convert 6 miles to yards.
    • Write: 6 miles1\frac{6 \text{ miles}}{1}
    • First conversion is from miles to feet:
      • Setup: 5280 feet1 mile\frac{5280 \text{ feet}}{1 \text{ mile}}
    • Second conversion from feet to yards:
      • Setup: 1 yard3 feet\frac{1 \text{ yard}}{3 \text{ feet}}
    • Simplification:
      • Miles cancel out, leaving feet.
    • Final calculation:
      • 6×5280 yards1×1×3\frac{6 \times 5280 \text{ yards}}{1 \times 1 \times 3}
      • 31680 yards3=10560 yards\frac{31680 \text{ yards}}{3} = 10560 \text{ yards}

Weight Conversions

Weight Conversion: Tons to Pounds

  1. Convert 6.3 tons to pounds.
    • Write as: 6.3 tons1\frac{6.3 \text{ tons}}{1}
    • Conversion: 1 ton=2000 pounds1\text{ ton} = 2000\text{ pounds}
    • Setup: 2000 pounds1 ton\frac{2000 \text{ pounds}}{1 \text{ ton}}
    • Calculation:
      • 6.3×2000=12600 pounds6.3 \times 2000 = 12600 \text{ pounds}

Weight Conversion: Ounces to Pounds

  1. Convert 86 ounces to pounds.
    • Write as: 86 ounces1\frac{86 \text{ ounces}}{1}
    • Conversion: 1 pound=16 ounces1\text{ pound} = 16 \text{ ounces}
    • Setup unit fraction: 1 pound16 ounces\frac{1 \text{ pound}}{16 \text{ ounces}}
    • Calculation:
      • Numerator: 86 pounds86 \text{ pounds}
      • Denominator: 1616
    • Final result:
      • 8616=5.375 pounds\frac{86}{16} = 5.375 \text{ pounds}

Additional Weight Example

  1. Convert 6400 ounces to tons.
    • Write as: 6400 ounces1\frac{6400 \text{ ounces}}{1}
    • Conversion to pounds first:
      • 1 pound16 ounces\frac{1 \text{ pound}}{16 \text{ ounces}}
    • Then to tons:
      • 1 ton2000 pounds\frac{1\text{ ton}}{2000 \text{ pounds}}
    • Calculation:
      • Resulting numerators: 6400 tons6400 \text{ tons}
      • Resulting denominator: 16×200016 \times 2000
    • Final result:
      • 640032000=0.2 tons\frac{6400}{32000} = 0.2 \text{ tons}

Capacity Conversions

Capacity Conversion: Quarts to Cups

  1. Convert 3 quarts to cups.
    • Write as: 3 quarts1\frac{3 \text{ quarts}}{1}
    • Conversion:
      • 1 quart=2 pints1\text{ quart} = 2\text{ pints}
    • Use unit fraction: 2 pints1 quart\frac{2 \text{ pints}}{1 \text{ quart}}
    • Second conversion:
      • 2 cups1 pint\frac{2 \text{ cups}}{1 \text{ pint}}
    • Simplification:
      • Result: 3×2×2=12 cups3 \times 2 \times 2 = 12 \text{ cups}

Capacity Conversion: Fluid Ounces to Pints

  1. Convert 72 fluid ounces to pints.
    • Write as: 72 fluid ounces1\frac{72 \text{ fluid ounces}}{1}
    • First, convert to cups:
      • Conversion: 1 cup8 fluid ounces\frac{1 \text{ cup}}{8 \text{ fluid ounces}}
    • Then, from cups to pints:
      • Conversion: 1 pint2 cups\frac{1 \text{ pint}}{2 \text{ cups}}
    • Simplification:
      • Result: 72 \text{ fluid ounces } \rightarrow \text{ total pints = 4.5 \text{ pints} $$

Conclusion

  • The examples illustrate the process of converting various measures across different contexts, ensuring simplification throughout the calculations.
  • These practical applications help solidify understanding of unit conversions within the American system of measurement.