+0

0
173
3  thank you for checking

Oct 4, 2019

#1
+1  if you could check this ne as well, wasnt sure what to put at the bottom, if you could help with that ?thank you again, this is the last three

Oct 4, 2019
#2
+3

First one

-9    is correct

Second one

-3R2 + 4R1  .....as before......I assume that the result goes in R1

-3R2   =  -24     3    -9

4R1  =    -12    20    8

___________

-36   23    -1

So.....the resulting matrix  is

-36   23   -1

8     1    3   Oct 4, 2019
#3
+3

The second one is easier if we identify what the parts of each martix represent

The first matrix

S          M        L

[ 1.50    2.50    6.50   ]    prices of the three sizes at store 1

[ 2.00    3.50    8.00   ]    prices of the three sizes at store  2

The second matrix

No. on shelf     No. in stockroom

of each size     of each size

10                    24              S

18                   48              M

6                     12              L

The first row of the first matrix x the first column of the second gives the total  price of the stock on the shelves in store 1....so  this is  entry a11  in the resulting matrix  =

(1.50)(10 ) + (2.50)*(18)  + (6.50)(6)  =  99

The first row of th first matrix x the secolumn of the second matrix gives the total price of the stock in the stockroom at store 1....this   is entry a12  in the resulting matrix =

(1.50)(24 ) + (2.50)(48) + (6.50)(12)  = 234

The second row of the first matrix x the first column of the second matrix  gives  the total price of the stock on the shelves at store 2......this is entry a21  in the resulting matrix =

(2.00)(10) + (3.50)(18) + (8.00)(6)  = 131

Finally.....second row of the first matrix x second column of the second matrix gives the total price of the stock in the stockroom of store 2.....this is entry a22 in the resulting matrix  =

(2.00)(24) + (3.50)(48) + (8.00)(12)  = 312

So     we have the following resultant (product) matrix :

Shelves   Stockroom

99            234       Store 1

131          312       Store 2

The rows represent  the  different stores

And the columns represent the location of the stock within each store   Oct 4, 2019
edited by CPhill  Oct 4, 2019