Answer:
330
Step-by-step explanation:
Given there are 11 books to be selected, and a final 7 has been selected. To find the number of possible ways, we calculate the selection combination;
[tex]Possible ways={T\choose S},T=Total, S= Selected\\\\={11\choose 7}\\\\=330[/tex]
Hence, the books can be selected in 330 different ways.