Question -
Answer -
If n = p, then the order of the matrix 
is
A p × 2 B 2 × n C n × 3 D p × n
Solution
The correct answer is B.
Matrix X isof the order 2 × n.
Therefore, matrix 7X isalso of the same order.
Matrix Z isof the order 2 × p, i.e., 2 × n [Since n = p]
Therefore, matrix 5Z isalso of the same order.
Now, both the matrices 7X and5Z are of the order 2 × n.
Thus, matrix 7X −5Z is well-defined and is of the order 2 × n.