Question

The cooperative stores of a particular school has 10 dozen physics books, 8 dozen chemistry books and 5 dozen mathematics books. Their selling prices are Rs. 8.30, Rs. 3.45 and Rs. 4.50 each respectively. Find the total amount the store will receive from selling all the items.

 

Answer 1

Stock of various types of books in the store is given by

 Physics     Chemistry     Mathematics

\[X = \begin{bmatrix}120 & 96 & 60\end{bmatrix}\]

Selling price of various types of books in the store is given by

\[Y = \begin{bmatrix}8 . 30 \\ 3 . 45 \\ 4 . 50\end{bmatrix}\begin{array}  \\Physics \\ Chemistry \\ Mathematics\end{array}\]  
\[\]

Total amount received by the store from selling all the items is given by

\[XY = \begin{bmatrix}120 & 96 & 60\end{bmatrix}\begin{bmatrix}8 . 30 \\ 3 . 45 \\ 4 . 50\end{bmatrix}\]

\[ = \begin{bmatrix}\left( 120 \right)\left( 8 . 30 \right) + \left( 96 \right)\left( 3 . 45 \right) + \left( 60 \right)\left( 4 . 50 \right)\end{bmatrix}\]

\[ = \begin{bmatrix}996 + 331 . 20 + 270\end{bmatrix}\]

\[ = \begin{bmatrix}1597 . 20\end{bmatrix}\]

Required amount = Rs 1597.20