Question

If $A$ is order $m\times n$, $B$ is of order $3\times p$ & $C$ is pf order $2\times 4$ if $AB+C$ is defined, find $m,n$ & $p$

Answer 1

$A_{m\times n}$
$B_{3\times p}$
$C_{2\times 4}$
$AB+C$ to be defined
$AB$ & $C$ should have same order.
$\therefore A{B}_{2\times 4}$
for $AB$ to be $2\times 4$
$n=3$; $m=2$, $p=4$