как сделать арифметику 5 класс страница 203 упр.605

1) 2/7х = 1
х = 1 : 2/7
х = 1/1 7/2
х = 7/2

2) 9х = 1
х = 1:9
х = 1/9

3) 1 5/8х = 1
х = 1 : 1 5/8 = 1/1 : 13/8 = 1/18/13
х = 8/13

4) 1/2х = 1
х = 1 : 1/2 = 1/12/1
х = 2

5) 7/15х = 1
х = 1 : 7/15 = 1/1 : 7/15 = 1/1 15/7
х = 1 6/7

6) 3 2/5х = 1
х = 1 : 3 2/5 = 1/1 : 17/5 = 1/15/17
х = 5/17

7) 100х = 1
х = 1:100
х = 1/100 = 0.01

8) 2/13х = 1
х = 1 : 2/13 = 1/1 13/2
х = 13/2 = 6 1/2 = 6.5