1) 636:х+139 = 145
636:х = 145-139
636:х = 6
х = 636:6
х = 106
2) 6×х-313 = 305
6×х = 305+313
6×х = 618
х = 618:6
х = 103
3) (223-х)×5 = 605
223-х = 605:5
223-х = 121
х = 223-121
х = 102
4) 822:(х-198) = 3
х-198 = 822:3
х-198 = 274
х = 274+198
х = 472
5) 3×(х+199) = 939
х+199 = 939:3
х+199 = 313
х = 313-199
х = 114
6) 666:(х-115) = 6
х-115 = 666:6
х-115 = 111
х = 111+115
х = 226
7) 7×(297-х) = 147
297-х = 147:7
297-х = 21
х = 297-21
х = 276
8) 624:(х+23) = 4
х+23 = 624:4
х+23 = 156
х = 156-23
х = 133
9) 864:х+213 = 221
864:х = 221-213
864:х = 8
х = 864:8
х = 108
10) 1512-204:х = 1510
204:х = 1512-1510
204:х = 2
х = 204:2
х = 104
11) 3×х+627 = 945
3×х = 945-627
3×х = 318
х = 318:3
х = 106