1) 4,4 - 4,15 = 0,25 = 1/4
2) 1/4 + 1 7/15 + 7/60 = 15/60 + 1 28/60 + 7/60 = 1 50/60 = 1 5/6
3) 1 5/6 : 3 2/3 = 11/6 : 11/3 = 3/6 = 1/2
4) 3 1/2 - 2,75 = 3 2/4 - 2 3/4 = 2 6/4 - 2 3/4 = 3/4
5) 3/4 : 0,2 = 3/4 : 1/5 = 15/4 = 3 3/4
6) 3 3/4 - 2 1/2 = 3 3/4 - 2 2/4 = 1 1/4
7) 1/2 : 1 1/4 = 1/2 : 5/4 = 4/10 = 2/5
Ответ 2/5 ( или 0,4 )