MTH 232

Section 10.1The Measurement Process

The Measurement Process

1. Choose the property, or attribute, of an object or event that is to be measured.

2. Select an appropriate unit of measurement.3. Select an appropriate measurement device.4. Express the measurement with the

appropriate units.

A History of Measurement• In early times, units of measurement were defined more

for convenience than for accuracy.• Many units of length correspond to parts of the human

body:1. The foot was the length of a human foot.2. The yard was the distance from a person’s nose to his

outstretched hand.3. The cubit was the length of a person’s arm from elbow to

fingertip.4. The hand was the width of a person’s hand with fingers not

spread.5. The span was the width of a person’s hand with fingers

spread.

More History

• Eventually, these convenient measurements became standardized to the English, or U.S., system we currently use.

• Some units (inch, foot, yard, mile) are more familiar than others (rod, furlong).

• Learning this system requires extensive memorization, and using the system involves computations with cumbersome numerical factors.

Quick Quiz!

• Fill in the blanks.1.____ inches = 1 foot2.____ feet = 1 yard3.____ feet = 1 mile4.____ feet = 1 rod5.____ feet = 1 furlong

Units of Area and Volume

• Area is the number of square units required to cover a region.

• Area is typically expressed in “square” units.• The acre, a unit of measurement that is equal

to 43,560 square feet, is also sometimes used.• Volume is the number of cubic units requires

to fill a space.• Volume is typically expressed in “cubic” units.

Units of Capacity

• Capacity is the volume that can be held in a container such as a bottle, pan, basket, or tank.

• Units of capacity include teaspoons, tablespoons, fluid ounces, cups, pints, quarts, gallons, and bushels (used for dry measure).

The Metric System

• Surprisingly, the Metric System has been around since the late 18th century.

• The official name is the International System of Units, or the SI System.

• It was standardized in the early 1980’s and is now used by nearly every industrialized nation in the world.

• The United States has not fully converted, which has led to many products having dual labeling.

How the Metric System Works

• The ratio of one unit of measure to another is also a power of 10.

• Each power of 10 is given a prefix (e.g., kilo-, milli-, or centi-) that modifies the fundamental unit (meter, liter, or gram).

• Conversion between units is a matter of moving the decimal point.

• “King Henry Doesn’t Usually Drink Chocolate Milk”