5 years ago A was 5 year elder than B.  After 6 years B will be 7 years elder than C.  After 8 years C will be 7 years elder than D.  If present age of D is 50 years old, then find the present age of A?

69

Present age of D = 50 years

Present age of C = (50 + 7) = 57 years

Present age of B = 57 + 7 = 64 years

Present age of A = 64 + 5 = 69 years