1) 12 : х = 20 : 512 5 = 20 х60 = 20 * хх = 60 / 20х = 3
2) 2 : 10 = х : 252 25 = 10 х50 = 10 * хх = 50 / 10х = 5
3) 21 : 3 = 35 : х21 х = 35 321х = 105х = 105 / 21х = 5
4) 18 : 3 = х : 418 4 = 3 х72 = 3 * хх = 72 / 3х = 24
1) 12 : х = 20 : 5
12 5 = 20 х
60 = 20 * х
х = 60 / 20
х = 3
2) 2 : 10 = х : 25
2 25 = 10 х
50 = 10 * х
х = 50 / 10
х = 5
3) 21 : 3 = 35 : х
21 х = 35 3
21х = 105
х = 105 / 21
х = 5
4) 18 : 3 = х : 4
18 4 = 3 х
72 = 3 * х
х = 72 / 3
х = 24