I need help with #4 a-d
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a repeating decimal is placed over 9's instead of 0's. for example: 0.23 = [tex]\frac{23}{100}[/tex], but 0.232323... = [tex]\frac{23}{99}[/tex]
a) x = 0.121212
b) 100(x) = 100(0.121212)
100x = 12.1212
c) 100x = 12.1212
- x = 0.1212
99x = 12
x = [tex]\frac{12}{99}[/tex]
d) -2[tex]\frac{12}{99}[/tex] = -2[tex]\frac{4}{33}[/tex] when simplified
The number is rational becase it has a repeating decimal