100 поинтов! Ребят, если кто-то понимает это, то объясните и Пожалуйста посчитайте пожалуйста​

1) 0.(5) = 5/9

0.(5) = x

5.(5) = 10x

10x - x = 5.(5) - 0.(5)

9x = 5

x = 5/9

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5) аналогично 1

1.(4)

1.(4) = x

10x = 14.(4)

10x - x = 14.(4) - 1.(4)

9x = 13

x = 13/9

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2 и 6  аналогично

2) 1.34(5) = 1211/900

100x = 134.(5)

1000x = 1345.(5)

1000x - 100x = 1345.(5) - 134.(5)

900x = 1211

x = 1211/900

6) 10x и 100x

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3 и 7 аналогично

3) 0.4(12) = 408/990

10x = 4.(12)

1000x = 412.(12)

1000x - 10x = 412.(12) - 4.(12)

990x = 408

x = 408/990 = 68/165

7) 10x и 1000x

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4 и 8 аналогично

4) 0.(9) = 1/1 = 1

0.(9) = x

9.(9) = 10x

10x - x = 9.(9) - 0.(9)

9x = 9

x = 9/9 = 1

8) 3.(9) = 4/1 = 4

x = 3.(9)

10x = 39.(9)

10x - x = 39.(9) - 3.(9)

9x = 36

x = 4