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Find the Rational Numbers Having the Following Decimal Expansion: 0 . ¯¯¯¯¯¯¯¯ 231 - Mathematics

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प्रश्न

Find the rational numbers having the following decimal expansion: 

\[0 .\overline {231 }\]

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उत्तर

\[0 . \overline {231 }\]

\[\text { Let } S = 0 . \overline {231 }\]

\[ \Rightarrow S = 0 . 231 + 0 . 000231 + 0 . 000000231 + . . . \infty \]

\[ \Rightarrow S = 0 . 231\left( 1 + {10}^{- 3} + {10}^{- 6} + . . . \infty \right)\]

\[\text { It is a G . P } . \]

\[ \therefore S = 0 . 231\left( \frac{1}{1 - {10}^{- 3}} \right)\]

\[ \Rightarrow S = \frac{231}{999}\]

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अध्याय 20: Geometric Progression - Exercise 20.4 [पृष्ठ ४०]

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आरडी शर्मा Mathematics [English] Class 11
अध्याय 20 Geometric Progression
Exercise 20.4 | Q 8.2 | पृष्ठ ४०

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