John was thrice as old as Tom 6 years ago. John will be 2 times as old as Tom in 4 years. How old is Tom today? Choose the correct choice
A) 12 B) 14 C) 16 D) 18 E) 20

Rationale: j - 6 = 3 ( t - 6 ) , so j = 3 t - 12 j + 4 = 2 ( t + 4 ) ( 3 t - 12 ) + 4 = 2 t + 8 t = 16 the answer is c .
Answer: C