Page 99 - ICSE Math 5

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We can write the fraction as 0.001 in the decimal
1000 Remember
form and read it as zero point zero zero one. 1
125 19 10 = 0.1 (one-tenth)
Similarly, = 0.125, = 0.019, and so on.
1000 1000 1
So far we have noticed that the number of digits after 100 = 0.01 (one-hundredth)
the decimal point is equal to the number of zeros in the 1 = 0.001 (one-thousandth)
denominator of the fraction. 1000

In a decimal number, the whole number is read in the usual
manner and the decimal part is read digitwise.
Let’s read the following fractions.
24 = 0.24 is read as zero point two four or twenty-four hundredths.
100
145 145
15 = 15 + = 15.145
1000 1000
It is read as fifteen point one four five or fifteen and one hundred forty-five thousandths.

Conversion of Fractions to Decimal Fractions and Decimal Numbers

Converting Fractions to Decimal Fractions

To convert a given fraction to a decimal fraction, we follow the given steps.

• Multiply the denominator of the given fraction with such a number that we get 10, 100,
1,000, etc., as the denominator. Also, multiply the numerator with the same number.
• We get an equivalent fraction having 10, 100, 1,000, etc., as the denominator which is a
decimal fraction.
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Example 1: Convert to a decimal fraction.
20
Solution: Convert the given fraction to equivalent fraction having 100 as the denominator.
9 9 × 5 45
= =
20 20 × 5 100
Converting Decimal Fractions to Decimal Numbers

To convert decimal fractions to decimal numbers, we follow the given steps.

• Count the number of zeros in the denominator.
• Write the numerator and starting from the right, put the decimal point before as many digits
as there are zeros in the denominator. If the denominator has more zeros than the digits in
the numerator, then write zeros after the decimal point to equate the number of digits.
Example 2: Convert the following to decimal numbers.
Remember
42 34
(a) (b) The number of digits after
100 1000
the decimal point should be
42 34 equal to the number of zeros
Solution: (a) = 0.42 (d) = 0.034 Notice the
100 1000 added zero. in the denominator.

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