Question

To promote making of toilets for women, an organisation tried to generate awarness through (i) house calls (ii) letters, and (iii) announcements. The cost for each mode per attempt is given below:
(i) Rs. 50 (ii) Rs. 20 (iii) Rs. 40
The number of attempts made in three village X, Y and Z are given below:
(i) (ii) (iii)
X 400 300 100
Y 300 250 75
Z 500 400 150
Find the total cost incurred by the organisation for three villages separately, using matrics.

Answer 1

$LetA=\left[\begin{array}{ccc}costof\left(i\right)& costof\left(ii\right)& costof\left(iii\right)\end{array}\right]=\left[\begin{array}{ccc}50& 20& 40\end{array}\right]B=\left[\begin{array}{ccc}400& 300& 500\\ 300& 250& 400\\ 100& 75& 150\end{array}\right]XYZA\times B=\left[\begin{array}{c}costofX\\ costofY\\ costofZ\end{array}\right]A\times B=\left[\begin{array}{ccc}50& 20& 40\end{array}\right]\left[\begin{array}{ccc}400& 300& 500\\ 300& 250& 400\\ 100& 75& 150\end{array}\right]=\left[\begin{array}{c}20000+6000+4000\\ 15000+5000+8000\\ 25000+8000+6000\end{array}\right]=\left[\begin{array}{c}30000\\ 23000\\ 39000\end{array}\right]$

Cost of X = 30,000

Cost of Y = 23,000

Cost of Z = 39,000