Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
Home  >>  CBSE XII  >>  Math  >>  Matrices
0 votes

Assume $X, Y, Z, W$ and $P$ are matrices of order $2\times n$, $3\times k$, $2\times p$, $n\times 3$ and $p\times k$, respectively. If $n = p$ then the order of the matrix $7X - 5Z$ is:

$$ (A) \quad p \times 2 \qquad \qquad (B) \quad 2 \times n \qquad \qquad (C) \quad n \times 3 \qquad \qquad (D) \quad p \times n $$
Can you answer this question?

1 Answer

0 votes
  • Multiplication of two matrices is defined only if the number of columns of the left matrix is the same as the number of rows of the right matrix.
The order of matrix X is $2\times n.$
The order of matrix Z is $2\times p.$
$7X-5Z$ can be defined only $X$ and $Z$ are of the same order, i.e, $n$ must equal $p$.
Thus the order of 7X-5Z is $2\times n$ or $2\times p$
(B) is the correct answer.
answered Feb 14, 2013 by sreemathi.v
edited Mar 1, 2013 by balaji.thirumalai

Related questions

Ask Question
student study plans
JEE MAIN, CBSE, AIPMT Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App