1) 6/11 = х/55 2) 3/8 = 45х 3) х/15 = 24/90
11х = 55 * 6 3х = 45 * 8 90х = 24 * 15
х = 330 : 11 х = 360 : 3 х = 360 : 90
х = 30 х = 120 х = 4
4) 8/х = 104/117 5) х/19,5 = 2/3 6) 37,8/х = 7/15
104х = 117 * 8 3х = 19,5 * 2 7х = 37,8 * 15
х = 936 : 104 х = 39 : 3 х = 567 : 7
х = 9 х = 13 х = 81