(a+b+c+d)/4=10,25
b=a+1
c=b+1=a+1
(a+b+c)/3=13→(a+a+1+a+2)/3=13→3a+3=39→3a=36→a=12
→b=13→c=14
(12+13+14+d)/4=10,25→39+d=41→d=2
Fie d=lungimea drumului
d=1/7×d+1/6×d+2,5
42d/42=6d/42+7d/42+105/42
42d=13d+105
29d=105
d=105/29
In prima zi a parcurs 1/6×105/42 (fă tu calculul)
A doua nu cred că mi-a dat bine dar nu am alta idee de rezolvare
