Education > Complete treatise on practical arithmetic and book-keeping

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DECIMAL FRACTIONS.
A DECIMAL is a fraction whose denominator is 1 with
some number of ciphers annexed ; as tV, or ttoW
Decimals are •written down without their denominators^
the numerators being sb distinguished as to evince what
the denominators are; which is done, by separating, by ai
point, so many of the right-hand figures from the rest as
there are ciphers in the denominator; the figures on the left-
hand side of the point being integers, and those on the right
decimals: So 44 >s written T3, and named 1 and 3 tenths A ■
is written 15'769, and named 15 and 769 thousandth- '
parts; and tVo9# is written ‘25, and named 25 hundredths,
or hundred parts.—But if there be not a sufficient number
of figures in the numerator, ciphers are prefixed to supply?
the defect: So t4o is written ‘01, that is, 1 hundredth; and
-roVcre thus, -0015, tliat is, 15 ten thousandths.
So that the denominator of a decimal is always a 1, with ,
as many ciphers as there are figures in the decimal.
Note 1. The 1st, 2d, 3d, 4th, &c. places of decimals, counting from- >:
the left-hand towards the right, are called the places of primes, seconds^ '
thirds, and fourths, &c. respectively.
2. Ciphers on the right-hand of decimals do no alter their value.
ADDITION, and SUBTRACTION of DECIMALS, i!
WRITE the proposed numbers under each other, accord-*
ing to the value of their places, as in whole numbers; in*!
which order the; decimal points will stand directly below*
each other: Then add or subtract as in whole numbers, plan
cing a decimal point in the sum or difference straight below -
the other points. ' ,
Examples in Addition.
1. What is the sum of 276, 39-218, 72014-9, 417, 5032,1 •
and 2214-29S?
2. What is the sum ©f 7530, 16-201, 3-0142, 957-13,
6-72819, and -03014 i
3. What is the sum of: 312-09, 3-5711, 7195-6, 7T493, '
9739-215, and 179?