above ans is correct i also solve it ans is 6

The above ans is correct .

Let us make it more clear : Ans. a/(b+c+d)+1+b/(c+d+e)+1+c/(d+a+b)+1+d/(a+b+c)+1-4 =(a+b+c+d){1/(b+c+d)........}-4=6×5/3 -4=10-4=6 .