Question

There are n books on a table. A student can take at least one book and at the most (n-1) books from these books in 62 different ways..... The total number of books on the table is :
A) 10
B)20
C)5
D)6
E) none
please help me out..I dont know how to deal with this. :(

Answer 1

i assume this means one or two or three or four or ...

Answer 2

i in which case the problem is not too bad
the only thing you are not allowed to do is pick all or none
if you could pick all (one way) or none (also one way) instead of 62 you would have 64 ways
since \(64=2^6\) your are on the sixth level of pascals triangle,

Answer 3

i.e. there are 6 books

Answer 4

So it means there are two possibilities which I shouldn't select... Rite ?
All or none...... So If the total possibilities without all or none are 62 so with all or none it will be 64.......

Answer 5

So where did it come ........2^6..... Why I need to do that.... ?
Is there any solution in which I can use permutation or combination etc... ? Please guide me......