Let x = 0.999… (that is, 0. 9). Using 10x − x, what is x?

1. 10x = 9.999…, so 10x − x = 9 → 9x = 9 → x = 1. So 0. 9 and 1 are the same number.

Let $x = 0.999$ … (that is, $0. \overline{9}$ ). Using $10 x - x$ , what is $x$ ?

Class 8Rational Numbers as DecimalsRational Numbers

10 x = 9.999

…, so

10 x - x = 9

→

9 x = 9

→

x = 1

. So

0. \overline{9}

and 1 are the same number.

Answer: C) 1

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