Номер 523.

1) 1/3 х+1/х=4/15

2) 1/х-1/7 х=2/7

3) 1/4 х+1/х=5/16

4) 1/х-1/9 х=2/9

5) 1/8 х+1/х=3/8

6) 1/х-1/5 х=2/15

1/3 х + 1/х = 4/15

1/3 х + 3/3 х = 4/15

4/3 х = 4/15

3 х = 4 : 4/15

3 х = 4 * 15/4

3 х = 15

х = 15 : 3

х = 5

1/х - 1/7 х = 2/7

7/7 х - 1/7 х = 2/7

6/7 х = 2/7

7 х = 6 : 2/7

7 х = 6 * 7/2

7 х = 3 * 7

7 х = 21

х = 21 : 7

х = 3

1/4 х + 1/х = 5/16

1/4 х + 4/4 х = 5/16

5/4 х = 5/16

4 х = 5 : 5/16

4 х = 5 * 16/5

4 х = 16

х = 16 : 4

х = 4

1/х - 1/9 х = 2/9

9/9 х - 1/9 х = 2/9

8/9 х = 2/9

9 х = 8 : 2/9

9 х = 8 * 9/2

9 х = 4 * 9

9 х = 36

х = 36 : 9

х = 4

1/8 х + 1/х = 3/8

1/8 х + 8/8 х = 3/8

9/8 х = 3/8

8 х = 9 : 3/8

8 х = 9 * 8/3

8 х = 3 * 8

8 х = 24

х = 24 : 8

х = 3

1/х - 1/5 х = 2/15

5/5 х - 1/5 х = 2/15

4/5 х = 2/15

5 х = 4 : 2/15

5 х = 4 * 15/2

5 х = 2 * 15

5 х = 30

х = 30 : 5

х = 6