accuracy in measurement, as for piston, bearing, and valve clearances or

tolerances, and in machining some parts, decimals in the 100ths and 1,000ths

of an inch are commonly used.

As was discussed in task 1, common fractions may be reduced to higher or to

lower terms. Suppose that it becomes desirable to reduce all fractions to a

standard denominator of 10, 100, 1,000, or even 100,000.

Then 1/4 would

become:

These common fractions are now decimal fractions.

But, instead of

simplifying the work, they have complicated it with long, unhandy

denominators. To relieve this complication, a symbol called a decimal point

is used.

This decimal point serves to eliminate the denominators.

The

problem fraction is then presented in its simplest form.

For instance,

25/100 becomes .25.

The decimal point has now taken the place of the

denominator, which makes it easier to work with.

3.

Definition of Terms

a.

to mark the beginning of the decimal fraction, or to separate it from a

whole number.

b.

as .025, is a pure decimal. The example reads twenty-five thousandths.

c.

This is a whole number and a decimal fraction.

For

instance, 1.256 is a mixed decimal.

It reads 1 and two hundred fifty-six

thousandths.

4.

Reading Decimals

Before attempting to read decimals, places should be learned.

A study of

figure 7 on the following page should help. The place in which you write a

decimal point is very important. Each integer (a whole number) in figure 7

is a number 3. Yet, no two of these 3's have like values. The first