1. (x-1,25)*4,5=27
4,5х-5,625=27
4,5х=27+5,625
4,5х=32,625
х=7,25
2. (x+19,64)*0,18=144
0,18х+3,5352=144
0,18х=144-3,5352
0,18х=140,4648
х=780,36
3. 5,6:x-6=34,03
5,6:х=34,03+6
5,6:х=40,03
х=40,03*5,6
х=224,168
4. x:100-1,2367=2,9633
х:100=2,9633+1,2367
х:100=4,2
х=420