Question

don't Spam

tell the correct answer​

Answer 1

$\large\underline{\sf{Solution-}}$

Given that,

In school,

Book shop has following number of books :

Chemistry = 10 dozen = 10 × 12 = 120 books

Physics = 8 dozen = 12 × 8 = 96 books

Economics = 10 dozen = 10 × 8 = 96 books

Selling price of book are as follow :

Chemistry = Rs 80

Physics = Rs 60

Economics = Rs 40

Let we assume that

Matrix A represents the quantity of books.

$\rm :\longmapsto\:A \: = \: \begin{gathered}\bf \left[\begin{array}{ccc}120&96&120\end{array}\right]\end{gathered}$

Matrix B represents the Selling price of respective books.

$\rm :\longmapsto\:B \: = \: \begin{gathered}\sf \left[\begin{array}{c}80\\60\\40\end{array}\right]\end{gathered}$

So,

Total amount received on Selling all the books is

$\rm \: = \: AB$

$\rm \: = \: \begin{gathered}\bf \left[\begin{array}{ccc}120&96&120\end{array}\right]\end{gathered}\begin{gathered}\sf \left[\begin{array}{c}80\\60\\40\end{array}\right]\end{gathered}$

$\rm \: = \: \: [120 \times 80 + 96 \times 60 + 120 \times 40]$

$\rm \: = \: \: [9600 + 5760 + 4800]$

$\rm \: = \: \: [20160]$

Hence,

Total amount received on Selling the books = Rs 20160.

Additional Information :-

1. Matrix multiplication is defined when number of columns of pre - multiplier is equals to number of rows of post - multiplier.

2. Matrix multiplication may or may not be Commutative.

3. Matrix multiplication is Associative, i.e A(BC) = (AB)C

4. There exist an Identity matrix such that AI = IA = A

Answer 2

Answer:

Yo Yo Yo

Shubh Ratri _/\_