Basic Mathematics for College Students

488 Chapter 5 Summary and Review

73. Convert 210 yards to miles. Give the exact answer
    and a decimal approximation, rounded to the
    nearest hundredth.


74. TRUCKING Large
    concrete trucks can
    carry roughly 40,500
    pounds of concrete.
    Express this weight in
    tons.

75.SKYSCRAPERS The Sears Tower in Chicago is

1,454 feet high. Express this height in yards.

76.BOTTLING A magnum is a 2-quart bottle of wine.

How many magnums will be needed to hold 50

gallons of wine?

SECTION 5.4 Metric Units of Measurement

The basic metric unit of measurement is the

meter,which is abbreviated m.

Longer and shorter metric units are created by

adding prefixesto the front of the basic unit,

meter.

DEFINITIONS AND CONCEPTS EXAMPLES

kilomeans thousands decimeans tenths

hectomeans hundreds centimeans hundredths

dekameans tens millimeans thousandths

Common metric units of length are the

kilometer, hectometer, dekameter, decimeter,

centimeter,and millimeter.Abbreviations are

often used when writing these units. See the

table on page 456.

1 km 1,000 m

1 hm 100 m

1 dam10 m 1 m1,000 mm

 1 m100 cm

 1 m 10 dm

A metric rulercan be used for measuring

lengths. On most metric rulers, each centimeter

is divided into 10 millimeters.

1234567

Centimeters

2 cm 43 mm 65 mm

10 mm

To convert from one metric unit of length to

another, we use unit conversion factors.

Convert 4 meters to centimeters.

To convert from meters to centimeters, we select a unit conversion

factor that introduces the units of centimeters and eliminates the units

of meters. Since there are 100 centimeters per meter, we will use:

To perform the conversion, we multiply.

Write 4 m as a fraction.

Then multiply by a form of 1:.

Multiply the fractions and simplify.

Thus, 4 meters = 400 centimeters.

 400 cm

Remove the common units of meters from

the numerator and denominator. The units

of cm remain.



4 m

1



100 cm

1 m

100 cm

1 m^

4 m

4 m

1



100 cm

1 m

This is the unit we want to introduce.

 This is the unit we want to eliminate (the original unit).

100 cm

1 m

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