(1)0.45时:30分=27分:30分=27÷30=0.9(2)2: 1 8 =2÷ 1 8 =16(3) 4 5 : 10 11 = 4 5 ÷ 10 11 = 22 25 (4) 5 9 : 7 9 = 5 9 ÷ 7 9 = 5 7 (5) 3 20 :0.45= 3 20 ÷0.45= 1 3 (6) 13 15 : 26 30 = 13 15 ÷ 26 30 =1.