Page 279 - ICSE Math 7

If the fractions to be compared are like fractions, then the fraction
with the greatest numerator is the largest.

Comparison of If the fractions to be compared are unlike fractions, then convert
Fractions them into like fractions and then compare.

If the fractions to be compared having same numerator, then the
fraction with the smaller denominator is the largest.

DECIMALS

Decimals

Decimal fractions Like Decimal Unlike Decimal
Fractions having denominator 10 Decimals having same number of The decimal numbers having
or higher powers of 10 decimal places different number of decimal places
3 7
Example: , Example: 14.23 and 5.43 Example: 14.3, 12.02 and 11.352
10 100

Terminating decimals Non-terminating decimals
While converting fraction into decimals, if the While converting fraction into decimal, if the
dividend is completely divisible by the divisor, dividend is not completely divisible, then the
then the decimal is terminating decimal. decimal is non-terminating decimal.
2 23
Example: = 0.4 Example: = 3.2857…
5 7

Approximation Significant figures
The process of expressing a decimal number These figures represent the total number of
up to a specific number of decimal places digits in a number

RATIONAL NUMBERS

Rational Numbers
p
Numbers of the from , where p and q are
q
2 − 5
integers and q ≠ 0. Example: and
3 6

Positive rational numbers Zero is neither a positive nor Negative rational numbers
Numerator and denominator are either a negative rational number Numerator and denominator have
both positive or both negative opposite signs
5 − 7 − 4 3
Example: , Example: ,
6 − 8 7 − 5

Equality of rational numbers Standard form
p r p
Two rational numbers and are A rational number is in standard
q s q
equal if and only if p × s = q × r. form if p, q are co-prime and q is a
positive integer.

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