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

Explanation

To solve the problem step by step, we will calculate the total amount the bookshop will receive from selling all the books.

### Step 1: Calculate the number of books in each subject
1. **Chemistry Books**:
- Number of dozens = 10
- Number of books = 10 dozens × 12 books/dozen = 10 × 12 = 120 books

2. **Physics Books**:
- Number of dozens = 8
- Number of books = 8 dozens × 12 books/dozen = 8 × 12 = 96 books

3. **Economics Books**:
- Number of dozens = 10
- Number of books = 10 dozens × 12 books/dozen = 10 × 12 = 120 books

### Step 2: Create matrices for the number of books and their selling prices
- Let matrix A represent the number of books:
\[ A = \begin{bmatrix} 120 \\ 96 \\ 120 \end{bmatrix} \]

- Let matrix B represent the selling prices:
\[ B = \begin{bmatrix} 80 \\ 60 \\ 40 \end{bmatrix} \]

### Step 3: Calculate the total amount received from selling the books
The total amount can be calculated by multiplying the number of books by their respective selling prices and summing them up:
\[ \text{Total Amount} = (120 \times 80) + (96 \times 60) + (120 \times 40) \]

### Step 4: Perform the calculations
1. **Chemistry**:
- \(120 \times 80 = 9600\)

2. **Physics**:
- \(96 \times 60 = 5760\)

3. **Economics**:
- \(120 \times 40 = 4800\)

### Step 5: Sum the amounts
Now, we add all the amounts together:
\[ \text{Total Amount} = 9600 + 5760 + 4800 \]
Calculating this step by step:
- \(9600 + 5760 = 15360\)
- \(15360 + 4800 = 20160\)

### Final Answer
Therefore, the total amount received by the bookshop is Rs 20,160.

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