1.
Decimal fractions: fractions in which
denominators are powers of 10 are known as decimal fractions.
Thus, 1/10= 1 tenth = 1; 1/100 = 1
hundredth = 0.1;
99/100 = 99 hundredths = 9; 7/1000= 7
thousandths = .007, etc.
2.
Conversion of a decimal into vulgar fraction:
put 1 in the denominator under the decimal point and annex with it as many
zeros as is the number of digits after the decimal point. Now, remove the
decimal point and reduce the fraction to its lowest terms.
Thus, 0.25 = 25/100 = ¼; 2. 008=
2008/1000 = 251/125.
3.
I. annexing zeros to the extreme right of a
decimal fraction does not change its value thus, 0.8 = 0.80= 0.800, etc.
II. if numerator and denominator of a
fraction contain the same number of decimal places, then we remove the decimal sign.
Thus,
1.84/2.99 = 184/299 =8/13; .365/584 = 365/584= 5/8
4.
Operations on decimal fractions:
I.
Addition and subtraction of decimal fractions:
the given numbers are so placed under each other that the decimal points lie in
one column. The numbers so arranged can now be added or subtracted in the usual
way.
II.
Multiplication of a decimal fraction b s power
of 10: shift the decimal point to the r right by as many places as is the power
of 10.
Thus, 5.9632 x 100= 596. 32;
0.073 x 1000 = 0. 030 x 1000 = 730.
III.
Multiplication of decimal fractions: multiply the
given numbers considering them
