Thermodynamics problem... calculate the bond enthalpy of C-Cl in CCl4

CCl₄ ---------> 4Cl (g) ; ΔvapH° = +30.5 KJ/mol----------------(1)
C(s)  + 2Cl₂ (g)  ---------> ΔfH° = -135.5 KJ/mol ------------------(2)
C (s) ----------> C(g); ΔaH° = 715 KJ/mol --------------------------(3)
Cl₂ (g) ---------->2Cl (g) ;ΔaH° = 242 KJ/mol --------------------(4)
   multiplying with 2 in equation (4)
2Cl₂(g) ---------->4Cl(g) ; ΔaH° = 484 KJ/mol 
       now add equations (3) and (4) 
C(s) + 2Cl₂(g) ------>C(g) + 4Cl , ΔH₁ = 715 + 484 = 1199 KJ/mol -----(5)
       now add reverse of equation (1) 
CCl₄ (g) ------> CCl₄ (l), ΔH₂ = -30.5 KJ/mol-------------(6)
CCl₄ (l) ---------> C(s) + 2Cl₂(g) ,ΔH₃ = 135.5 KJ/mol---------(7)
     adding equations (5), (6) and (7) 
CCl₄ (g) --------> C(g) + 4Cl , ΔH = 135.5 - 30.5 + 1199 = 1304 KJ/mol
      now bond enthalpy  of C --- Cl is 1/4 of ΔH
                         Cl
                          |
      Cl------------ C ------------ Cl
                         |
                        Cl
 now, bond enthalpy = 1304/4 = 326 KJ/mol