Ten books are arranged in a row on a bookshelf. A student has to select three out of these ten books in such a way that no two books selected by him must have been lying adjacently. In how many ways can he make the selection?

1) 56
2) 64
3) 72
4) none of these

• 8c3=56ways
• 11 years agoHelpfull: Yes(0) No(0)