Average age of A and B is 30 Years, that of B and C is 32 Years and the average age of C and A is 34 Years. The age of C is:

Average of A & B is 
( A+B) /2 = 30  ⇒ A+B=60 ⇒ A= 60 – B —- (i) 
( B+C)/2 = 64 ⇒B+C = 64 ⇒ B= 64 – C—- ( ii ) 
Putting value of B in equation ( i ) 
⇒ A= 60 – 64 +C ⇒ A = -4 + C —– ( iii) 
( C+A)/2 = 34  ⇒ C+A=68 ⇒ C = 68 – A —–(iv)
Puuting value of A from eaquation ( iii) to eq. (iv)
⇒ C= 68 +4 -C ⇒ C =36