Page 45 - ICSE Math 7
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Example 3: Convert the following decimals into fractions.
(a) 27.9 (b) 0.052
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Solution: (a) 27.9 = 10 (One digit after the decimal point, therefore one
zero in the denominator)
(b) 0.052 = 52 = 13 ( Three digits after the decimal point)
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Comparison of Decimals
We use the following steps to compare two decimal numbers.
Step 1: Express the given decimals as like decimals.
Step 2: Compare the whole parts first. The number with the greater whole part is greater. If the
whole part of the numbers are equal then go to the next step (i.e., Step 3).
Step 3: Compare the tenths place, the decimal with the greater tenth digit is greater. If the tenth place
is also equal then compare the hundredths place and so on till you get a different place.
Example 4: Which is greater?
(a) 0.05 or 0.02 (b) 3.84 or 3.809
(c) 0.5 or 0.08 (d) 2.931 or 2.934
Solution: (a) 0.05 and 0.02 are like decimals. The whole part of both the decimal numbers is 0.
Hence, we compare their tenths place which are also equal, i.e., 0 in both cases.
Now we compare the digits in their hundredth place.
Since 5 > 2, therefore 0.05 > 0.02.
(b) Expressing 3.84 and 3.809 as like decimals, we get 3.840 and 3.809. The whole
part of both the decimal numbers is equal to 3.
Hence, we compare their tenths place which are also equal, i.e., 8 in both cases.
Now we compare the digits in their hundredth place.
Since 4 > 0, therefore 3.84 > 3.809.
(c) Expressing 0.5 and 0.08 as like decimals, we get 0.50 and 0.08. The whole part of
both the decimal numbers is 0.
Hence, we compare the digits in their tenth place.
Since 5 > 0, therefore 0.50 > 0.08.
(d) 2.931 and 2.934 are like decimals.
We compare the digits in their hundredth place.
Since 1 < 4, therefore 2.931 < 2.934.
Fundamental Operations on Decimals
Addition of decimals
To add decimals, convert all the decimals into like decimals, i.e., decimals with the same number of
digits after the decimal point. Write the decimals to be added one below the other with the decimal
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