Consider the following information regarding the number of men and women workers in three factories I. II and III
Men Workers |
Women Workers |
|
I |
30 |
25 |
II |
25 |
31 |
III |
27 |
26 |
Represent the above information in the form of a 3 x 2 matrix. What does the entry in the third row and second column represent ?
The given information is
Factory |
Men Workers |
Women Worker: |
I |
, 30 |
25 |
II |
' 25 |
31 |
III |
27 |
26 |
The information is represented in the form of a 3 X 2 matrix as follows :
The entry in the third row and second column represents the number of women workers in factory III.
If a matrix has 8 elements, what arc the possible orders it can have ?
We know' that if a matrix is of order m x n, it has mn elements. Therefore, for finding all possible orders of a matrix with 8 elements, we will find all ordered pairs of natural numbers, whose product is 8.
∴ all possible ordered pairs are (1.8), (8, I), (4, 2). (2, 4)
∴ possible orders are I x 8, 8 x 1, 2 x 4, 4 x 2.
Number of elements = 12
∴possible orders of the matrix are
1 x 12, 12 x 1,2 X 6. 6 x 2,3 x 4,4 x 3
If numbers of elements = 7, then possible orders are 1 x 7. 7 x 1
Let A = [a i] be required 3 x3 matrix
where a,ij , = 2 i – 3 j
∴ a11, = 2–3 = –1. a12 = 2–6 = 4. a13,= 2–9 = 7
a21 = 4 — 3 = 1. a22 = 4 — 6 = —2 . a23 = 4 –9 = 5
a31 = 6 – 3 = 3, = 6 – 6 = 0 , a33 = 6 – 9 = –3