Ответ:

Пошаговое объяснение:

7/15 = x/45

15*x = 45*7

15x = 315

x = 315 : 15

x = 21

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9/x = 3/7

3*x = 9*7

3x = 63

x = 63 : 3

x = 21

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x : 2 3/23 = 3 1/7 : 1/4

1/4 * x = 3 1/7 * 2 3/23

1/4 * x = 22/7 * 49/23

1/4 * x = 154/23

x = 154/23 * 4/1

x = 616/23

x = 26 18/23

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№2

2 4/7 * 1 5/9 = 18/7 * 14/9 = 4

1 7/9 * 2 1/4 = 16/9 * 9/4 = 4

4 = 4 ;

равенство верно