Basic Mathematics for College Students

486 Chapter 5 Summary and Review

To perform the conversion, we multiply.

Write 9,000 lb as a fraction. Then

multiply by a form of 1:.

Multiply the fractions.

There are two ways to complete the solution. First, we can remove any

common factors of the numerator and denominator to simplify the

fraction. Then we can write the result as a mixed number.

A second approach is to divide the numerator by the denominator and

express the result as a decimal.

Thus, 9,000 pounds is equal to 4 (or 4.5 tons).

1

2

tons

9,000

2,000

tons 4.5 tons

9,000

2,000

tons

9 1,000

1

2 1,000

1

tons

9

2

tons 4

1

2

tons



9,000

2,000

ton

Remove the common units of pounds

from the numerator and denominator.

The units of tons remains.



9,000 lb

1

1



1 ton

2,000 lb

1

1 ton

2,000 lb^

9,000 lb

9,000 lb

1



1 ton

2,000 lb

The American system of measurement uses the

units ofounce, cup, pint, quart,and gallonto

measure capacity.

1 c = 8 fl oz 1 pt = 2 c

1 qt = 2 pt 1 gal = 4 qt

A list of unit conversion factors for American

units of capacity is given on page 449.

Some conversions require the use oftwo(or

more) unit conversion factors.

Convert 5 gallons to pints.

There is not a single unit conversion factor that converts from gallons

to pints. We must use two unit conversion factors.

Since there are 4 quarts per gallon, we can convert 5 gallons to quarts

by multiplying by the unit conversion factor. Since there are 2 pints

per quart, we can convert that result to pints by multiplying by the unit

conversion factor.

Do the multiplication:.

Thus, 5 gallons 40 pints.

 40 pt 5  4  2  40

Remove the common units of gallons

and quarts in the numerator and

denominator. The units of pints remain.



5 gal

1



4 qt

1 gal



2 pt

1 qt

5 gal

5 gal

1



4 qt

1 gal



2 pt

1 qt

2 pt

1 qt^

4 qt

1 gal^

The American (and metric) system of

measurement use the units ofseconds, minutes,

hours,and daysto measure time.

1 min = 60 sec 1 hr = 60 min 1 day = 24 hr