A company sells five models of computers through three retail outlets. The inventories are represented by S. The wholesale and retail prices are represented by T. Compute ST and interpret the result.

Question

S= 4 4 3 4 2
0 0 4 4 4
0 4 3 3 0
t = wholesale retail
$840 $1100
$1200 $1350
$1450 $1650
$2650 $3000
$3050 $3200

Answer 1

wholesale:
$840
$1200
$1450
$2650
$3050

retail:
$1100
$1350
$1650
$3000
$3200

Answer 2

Since S is 5x3 and T is 5x2, ST is undefined.
But, U = ST^T is a matrix whose (i,j) element is the total revenue for model i , wholesale or retail (j=1 or 2)

Answer 3

never mind. S is 3x5, so ST is defined.