(11 + 31 + 23) : 3 = 21,67
(15+28+27) : 3 = 23,3
220: 1,2,4,5,10,11,20,22,44,55,110,
284: 1,2,4,71,142,
А) -11,9+6,7-5,8-3,6= -14,6
б) -17,6+3,9+8,4-9,6-4,2= -19,1
в) -60/7-47/7+33/5+47/5= -107/7+80/5=16-107/7=112/7-107/7=5/7
г)
д) -|4/9-5/18+7/9|-|3/54-16/54|=-|8/18-5/18+14/18|-|-13/54|=-17/18-13/54= -51/54-13/54= -64/54= -32/27= -1 5/27
Дроби: 2/5 3/6 4/7 5/8 7/10
Задача: 12:6*7=14(тонн)
НОД(180,396)=2*2*3*3=36 НОК(180,396)=396*5=1980 наверное так