The bookshop of a particular school has 10 dozen chemistry books, 8 dozen physics books, 10 dozen economics books. Their selling prices are Rs 80, Rs 60 and Rs 40 each respectively. Find the total amount the bookshop will receive from selling all the books using matrix algebra.

Assume X, Y, Z, W and P are matrices of order 2 × n, 3 × k, 2 × p, n × 3 and p × k, respectively.

It is given that the bookshop of a particular school has 10 dozen chemistry books, 8 dozen physics books, 10 dozen economics books.

Their selling prices are Rs 80, Rs 60 and Rs 40 each respectively.


The total amount of money that will be received from the sale of all these books can be represented in the form of a matrix as:



= 12[10 × 80 + 8 × 60 + 10 × 40]


= 12(800 + 480 + 400)


= 12(1680)


= 20160


Therefore, the bookshop will receive Rs. 20160 from the sale of all these books.


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