1) 4 5/12 - 3 7/18=4 15/36 - 3 14/36 = 1 1/36
2) 1 1/36:9,25=37/36:37/4=37/36 * 4/37=1/9
3) 1/9 + 5/6 = 2/18 +15/18 = 17/18
4)0,4 + 1/8=0,4+0,125=0,525
5) 0,525+0,75=1,275
6) 1,275*2/3=0,425*2=0,85
7)17/18 :0,85= 17/18 : 17/20 =17/18* 20/17 = 10/9=1 1/9