Вычислите 4:7/11 15/17:5 4/9:1/3 33/8:21/2

4 : 7/11 = 4/1 * 11/7 = 88/7 = 12 4/7,15/17 : 5 = 15/17 * 1/5 = 3/17,4/9 : 1/3 = 4/9 * 3 = 4/3 = 1 1/3,33/8 : 21/2 = 33/8 * 2/21 = 11/28