Matrix Multiplication
TURN THIS PAGE IN
Team Name: ______ KEY _______
Members Present: ________________________________________________________________
Section: __________
Part I
1.
Cost = 4 roses $3/rose + _ 2 _ carnations $_ 1.5
_/carnation + _ 3 _daisies $_ 2 _/daisy
+ _ 1 orchid __ _ $2.50/orchid __ = _ $23.50
__
2.
Matrix for Cost:
$
 r c d o
.
2 .

Matrix for Number of Flowers:
# r c
 
2 d 3 o 1
3. __ 2 _______ __ 3 _______ = __ 6 ________
The value represents __ the total cost of the daisies in the arrangement.
______________________
5.
a.
C = __ [23.5] __ b.
The value in C represents _ the total cost of the arrangement.
_______________
Part II
1.
If a matrix multiplication is not possible, enter DNE (does not exist) for the size
a.
Size: __ DNE _____ b. Size: __ 3 4 _____ c.
Size: __ 5 4 _____
d. Size: __ DNE _____ e. Size: __ 4 5 _____
2. a.
c
23
=
__ 2(2) + 1(3) ___________ = __ 7 _____ b.
c
41
=
__ 0(1) 1( 1) __________ = __ 1 _____
©Texas A&M University Page 1

Matrix Multiplication
3. a.




1 2
3 4
 
  a b c d



 




1
3
   a 4 c c
1
3 b b
2
4 b.



 a b c d
 
 
1 2
3 4 







 a

3 b 2 a

4 b c

3 d 2 c

4 d 



Are they equal? __ No _______ d d








 a

2 c b

2 d
3 a

4 c 3 b

4 d 



Part III
1. a. The product NC IS or IS NOT numerically possible. (Circle one.)
If possible, the dimensions of the product NC are __ 2 __ __ 1 __.
d. The product NC IS or IS NOT meaningful. (Circle one.) e.
The rows of the product matrix represent _ the cities _ and the column(s) represent_ dollars _.
$ f.
NC

D
F




254
230




2. a.
_the total revenue for the flower shop in Dexton________________________ b.
_the total revenue for the flower shop in Foundly________________________
3.
_This product yields the same information as NC but the matrix is a transpose
of matrix NC ._____________________________________________________
Part IV
1. _ XY is meaningless._________________________________________________
__________________________________________________________________
2. _The entries in matrix YX represent the cost to manufacture a single chair,
_ table, and desk at each one of the plants.______________________________
C T D
3.
M 30 14
F 51 16
N 64 29
36
36
74







©Texas A&M University Page 2