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Write the number 0.21212121 as a fraction

User Fatmir
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1 Answer

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If is 0.21212121 then


0.\underbrace{21212121}_(8)=\frac{21212121}{1\underbrace{00000000}_(8)}

If is 0.21212121... then


x=0.21212121...\ \ \ |\cdot100\\100x=21.21212121...\\\\100x-x=21.21212121...-0.21212121...\\\\99x=21\ \ \ |:99\\\\x=(21)/(99)\\\\x=(21:3)/(99:3)\\\\x=(7)/(33)\\\\0.21212121...=(7)/(33)

User Jan Sverre
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