Verified answer

0,(27) = x

27,(27) = 100x

100x - x = 27,(27) - 0,(27)

99x = 27

x = 27/99 = 3/11

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3,6(7) = x

36.(7) = 10x

367.(7) = 100x

100x - 10x = 367.(7) - 36.(7)

90x = 331

x = 331/90