So c=a+7

e=a+7+7=a+ 14

B and d are smaller 1 and larger 1 than c, respectively.

So b=c- 1, d=c+ 1.

a+b+c+d+e=50

a+(c- 1)+c+(c+ 1)+e = 50

a+3c+e=50

a+3(a+7)+(a+ 14)=50

5a+35=50

a=3