900см =9000мм
900000мм-9000мм=891000мм
39038,82=39039
429,33=429
92887=92887
195000=195000
1 кг= 1000 г
0,25 кг = 250000 г
64/70 - х + 26/70 = 5/70
64/70 - х = 5/70 - 26/70
64/70 - х = - 21/70
х = 64/70 - (- 21/70)
х = 85/70
-----------------------------------
64/70 - 85/70 + 26/70 = 5/70
- 21/70 + 26/70 = 5/70
5/70 = 5/70