540 : x = 380 : 19
540/х=20
х=540/20
х=27
540/27=380/19
20=20
х * 6 = 18000 +24
6х=18024
х=18024/6
х=3004
3004*6=18000+24
18024=18024
3480 -х = 2190:3
3480 -х =730
х=3480-730
х=2750
3480-2750=730
730=730
х+ 2010 = 3001 *4
х+ 2010 = 12004
х=12004-2010
х=9994
9994+2010=3001*4
12004=12004