Люди решить все кроме в первом (а)

Пошаговое объяснение:

1) 3 + 4/6 = 3 + 2/3 = 3 2/3

2)

x/14 = 4/7

7*x = 14*4

7x = 56

x = 56 : 7

x = 8

x/6 = 98/21

21x = 98*6

21x = 588

x = 588 : 21

x = 28

45:5x = 9 : 4

5x*9 = 45*4

45x = 180

x = 180:45

x = 4

4 : 2 2/7 = 5/8 : x

4*x = 5/8 * 2 2/7

4x = 5/8 * 16/7

4x = 10/7

x = 10/7 * 1/4

x = 5/14

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