P and Q undertake to do a piece of job for Rs.1200. P alone can do it in 12 days while Q alone can do it in 16 days. With the help of R , they finish it in 6 days. Find the share of P,Q & R. a) 400,600,200 b) 200,400,600 c) 450,400,250 d) 600,450,150