Page 25 - Past Year

23 | P a g e

1 

,
(ii) If C B AB findC .

 2  4 3   1 5 m 



(b) Given A    x 2  1 and B   1  8  5 .



  2  3 1     1  14  8 
(i) If the minor for element b 32 is -3, find m.

(ii) If the cofactor for element a 13 is -1, find x.

T
(iii) Hence, find B  2A .

17. Syarikat Dari Mata Ke Hati produces three types of souvenirs; key-chain, fridge-magnet
and book-mark. In a day, three shifts of workers are used to produce the company’s

products. The number of each type of souvenirs produced can be summarized as follows.

Workers’ ratio Number of
Types of
souvenirs
souvenirs Shift I Shift II Shift III
produced

Key-chain 2 1 1 180
Fridge-magnet 1 3 2 300

Book-mark 2 1 2 240

(a) Write the system of linear equations in the form of matrix equation, AX  B where

A is the coefficient matrix, X is the variable matrix and B is the constant matrix.
(b) Using Cramer’s Rule, find the number of workers needed for each shift to produce

the souvenirs.

(c) To fulfill the demand for peak season, the company increases the number of
workers up to 100 workers for each shift. Calculate the number of each souvenir

produced per day during the season.