80 ! сложите дроби: 1\5+8\25+7\25, 3\49+5\7+4\49, 31\80+3\16+39\80, 7\15+2\15+1\5, 1\27+5\9+1\3, 3\8+5\12+1\24

1/5 + 8/25 + 7/25 = 5/25 + 8/25 + 7/25 = (5+8+7)/25 = 20/25 = 4/5

3/49 + 5/7 + 4/49 = 3/49 + 35/49 + 4/49 = (3+35+4)/49 = 42/49 = 6/7

31/80 + 3/16 + 39/80 = 31/80 + 15/80 + 39/80 = (31+15+39)/80 = 85/80 = 17/16 = 1 целая 1/16

7/15 + 2/15 + 1/5 = 7/15 + 2/15 + 3/15 = (7+2+3)/15 = 12/15 = 4/5

1/27 + 5/9 + 1/3 = 1/27 + 15/27 + 9/27 = (1+15+9)/27 = 25/27

3/8 + 5/12 + 1/24  = 9/24 + 10/24 + 1/24 = (9+10+1)/24 = 20/24 = 5/6

1\5+8\25+7\25=(5+8+7)/25=20/25=0.8
 3\49+5\7+4\49=(3+35+4)/49=42/49=6/7
7/15 + 2/15 + 1/5 = (7+2+3)/15 = 12/15 = 4/5
 31\80+3\16+39\80=(31+15+39)/80=85/80=17/16=1 1/16
1\27+5\9+1\3=(1+15+9)/27=25/27
 3\8+5\12+1\24=(9+10+1)/24=20/24=5/6