From 6 different novels 4 novels can be chosen =6C4 ways And from 4 different dictionaries 1 can be chosen =3C1 ways ∴ From 6 different novels and 3 different dictionaries, 4 novels and 1 dictionary can be chosen =6C4×3C1 ways Let 4 novels are N1,N2,N3,N4 and 1 dictionary is D1. Dictionary should be in the middle. So the arrangement will be like this −−D1−− On those 4 blank places 4 novels N1,N2,N3,N4 can be placed. And 4 novels can be arrange 4 ! ways. ∴ Total no of ways =6C4×3C1×4!=1080