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Find the rational number equivalent to 0.490 with 90 repeating?

User Catriona
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1 Answer

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x=0.4\overline{90}=0.4909090\ldots

10x=4.\overline{90}=4.909090\ldots

10x-4=0.\overline{90}=0.909090\ldots

100(10x-4)=90.\overline{90}=90.909090\ldots

100(10x-4)-(10x-4)=90.\overline{90}-0.\overline{90}=90

1000x-400-10x+4=90

990x=486

x=(486)/(990)=(27)/(55)
User Weimar
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