Question

The number of all possible matrices of order 3 x 3 with each entry 0 or 1 is
(A) 27
(B) 18
(C) 81
(D) 512

Answer 1

There are 9 entries in a 3 x 3 matrix. Each place can be filled with 0 or 1.
∴ 9 places can be filled in 2⁹ = 512 ways.
Number of such matrices = 512.