Anuj and Manoj can together paint their house in 30 days. After working for 20 days Anuj has to go out and Manoj finishes the remaining work in the next 30 days. If Manoj had gone away after 20 days instead of Anuj, then Anuj would have completed the remaining work in `15\ d a y s` b. `20\ d a y s` c. `25\ d a y s` d. `35\ d a y s`