20 : (6 3/11 + 1 8/11) + (7 2/5 - 5,8) : 5 = 2 41/50 (или 2,82)
1) 6 3/11 + 1 8/11 = 7 11/11 = 8,
2) 20 : 8 = 20/8 = 5/2 = 2 1/2,
3) 7 2/5 - 5,8 = 7 4/10 - 5 8/10 = 6 14/10 - 5 8/10 = 1 6/10 = 1 3/5,
4) 1 3/5 : 5 = 8/5 * 1/5 = 8/25,
5) 2 1/2 + 8/25 = 2 25/50 + 16/50 = 2 41/50 (или = 2 82/100 = 2,82)
20 : (6 3/11 + 1 8/11) + (7 2/5 - 5,8) : 5 = 2 41/50 (или 2,82)
1) 6 3/11 + 1 8/11 = 7 11/11 = 8,
2) 20 : 8 = 20/8 = 5/2 = 2 1/2,
3) 7 2/5 - 5,8 = 7 4/10 - 5 8/10 = 6 14/10 - 5 8/10 = 1 6/10 = 1 3/5,
4) 1 3/5 : 5 = 8/5 * 1/5 = 8/25,
5) 2 1/2 + 8/25 = 2 25/50 + 16/50 = 2 41/50 (или = 2 82/100 = 2,82)