Ray's New Higher Arithmetic · Arts. 209–217 · Unit 11: Compound Denominate Numbers

52. The metric system

Goal: Your student names the metric units and prefixes, converts within the metric system by moving the point, and uses the book's table of metric and U. S. values.

⏱ About 40 minutes · 7 steps

Open it at the Internet Archive ↗

You'll need

  • The book
  • A slate, small whiteboard or scrap paper
  • A notebook and pencil

What's in the book

The metric system: its history, the units (meter, ar, liter, gram, and others), the prefixes milli, centi, deci, deka, hekto, kilo and myria, tables of length, surface, capacity and weight, and a table of legal and approximate U. S. values. A topical outline of the measures closes the section.

The lesson, step by step

  1. Warm-up

    Ask: How many centimeters in a meter? Millimeters in a meter?

  2. The idea

    Read:

    The Metric System is an outgrowth of the French Revolution of 1789.

    The Metric System is a decimal system of weights and measures.

    The book's spelling is a little different from ours: ar for are, hektometer for hectometer.

  3. Prefixes

    Read the list: milli .001, centi .01, deci .1; deka 10, hekto 100, kilo 1000, myria 10000. Your student makes a chart from the smallest to the largest.

  4. Units

    Read:

    The Meter is the unit of Length, and is the denomination used in all ordinary measurements.

    The Ar (pro. ar) is the unit of Land Measure; it is a square, each side of which is 10 meters

    The Liter (pro. le'ter) is the unit of Capacity.

    The Gram (pro. gram) is the unit of Weight.

  5. U. S. values

    Read:

    The following table presents the legal and approximate values of those denominations

    Pick out: a meter is 39.37 inches, a kilometer .62137 mile, a liter 1.0567 quarts, a kilogram 2.2046 pounds, a hektar 2.471 acres.

  6. Practice

    Your student converts: 3.5 km to meters; 2400 grams to kilograms; 5 meters to inches (book's value); 10 kilograms to pounds; 40 hektars to acres.

  7. Wrap-up

    Ask: Why is it easy to change units in the metric system? (Move the decimal point.)

Answers to the book's problems

Practice: 3.5 km = 3500 m; 2400 g = 2.4 kg; 5 m = 196.85 in.; 10 kg = 22.046 lb.; 40 Ha = 98.84 acres.

Worked out for this site from the scan. If a number in your copy differs, trust the book.

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