Reena can do a piece of work in 16 days. Ragini can do the same work in 12 $\frac{4}{5}$ days while Gudia can do in 32 days. All of them started to work together but Reena leaves after 4 days. Ragini leaves the job 3 days before the completion of the work. How long would the work last?

20 men can finish a work in 30 days